{"Version": "v4.15.0", "section": "Language", "text": "implements `Simp.Config.implicitDefEqsProofs`. When `true` (default: `true`), `simp` will **not** create a proof term for a rewriting rule associated with an `rfl`-theorem. Rewriting rules are provided by users by annotating theorems with the attribute `@[simp]`. If the proof of the theorem is just `rfl` (reflexivity), and `implicitDefEqProofs := true`, `simp` will **not** create a proof term which is an application of the annotated theorem.", "pull request": "4595"}
{"Version": "v4.15.0", "section": "Language", "text": "avoid negative environment lookup", "pull request": "5429"}
{"Version": "v4.15.0", "section": "Language", "text": "ensure `instantiateMVarsProfiling` adds a trace node", "pull request": "5501"}
{"Version": "v4.15.0", "section": "Language", "text": "adds a feature to the the mutual def elaborator where the `instance` command yields theorems instead of definitions when the class is a `Prop`.", "pull request": "5856"}
{"Version": "v4.15.0", "section": "Language", "text": "unset trailing for `simpa?` \"try this\" suggestion", "pull request": "5907"}
{"Version": "v4.15.0", "section": "Language", "text": "changes the rule for which projections become instances. Before, all parents along with all indirect ancestors that were represented as subobject fields would have their projections become instances. Now only projections for direct parents become instances.", "pull request": "5920"}
{"Version": "v4.15.0", "section": "Language", "text": "make `all_goals` admit goals on failure", "pull request": "5934"}
{"Version": "v4.15.0", "section": "Language", "text": "introduce synthetic atoms in bv_decide", "pull request": "5942"}
{"Version": "v4.15.0", "section": "Language", "text": "adds a new definition `Message.kind` which returns the top-level tag of a message. This is serialized as the new field `kind` in `SerialMessaege` so that i can be used by external consumers (e.g., Lake) to identify messages via `lean --json`.", "pull request": "5945"}
{"Version": "v4.15.0", "section": "Language", "text": "`arg` conv tactic misreported number of arguments on error", "pull request": "5968"}
{"Version": "v4.15.0", "section": "Language", "text": "BitVec.twoPow in bv_decide", "pull request": "5979"}
{"Version": "v4.15.0", "section": "Language", "text": "simplifies the implementation of `omega`.", "pull request": "5991"}
{"Version": "v4.15.0", "section": "Language", "text": "fix style in bv_decide normalizer", "pull request": "5992"}
{"Version": "v4.15.0", "section": "Language", "text": "adds configuration options for `decide`/`decide!`/`native_decide` and refactors the tactics to be frontends to the same backend. Adds a `+revert` option that cleans up the local context and reverts all local variables the goal depends on, along with indirect propositional hypotheses. Makes `native_decide` fail at elaboration time on failure without sacrificing performance (the decision procedure is still evaluated just once). Now `native_decide` supports universe polymorphism.", "pull request": "5999"}
{"Version": "v4.15.0", "section": "Language", "text": "changes `bv_decide`'s configuration from lots of `set_option` to an elaborated config like `simp` or `omega`. The notable exception is `sat.solver` which is still a `set_option` such that users can configure a custom SAT solver globally for an entire project or file. Additionally it introduces the ability to set `maxSteps` for the simp preprocessing run through the new config.", "pull request": "6010"}
{"Version": "v4.15.0", "section": "Language", "text": "improves the validation of new syntactic tokens. Previously, the validation code had inconsistencies: some atoms would be accepted only if they had a leading space as a pretty printer hint. Additionally, atoms with internal whitespace are no longer allowed.", "pull request": "6012"}
{"Version": "v4.15.0", "section": "Language", "text": "removes the `decide!` tactic in favor of `decide +kernel` (breaking change).", "pull request": "6016"}
{"Version": "v4.15.0", "section": "Language", "text": "removes @[specilize] from `MkBinding.mkBinding`, which is a function that cannot be specialized (as none of its arguments are functions). As a result, the specializable function `Nat.foldRevM.loop` doesn't get specialized, which leads to worse performing code.", "pull request": "6019"}
{"Version": "v4.15.0", "section": "Language", "text": "makes the `change` tactic and conv tactic use the same elaboration strategy. It works uniformly for both the target and local hypotheses. Now `change` can assign metavariables, for example:\n```lean\nexample (x y z : Nat) : x + y = z := by\n  change ?a = _\n  let w := ?a\n  -- now `w : Nat := x + y`\n```", "pull request": "6022"}
{"Version": "v4.15.0", "section": "Language", "text": "fixes a bug where the monad lift coercion elaborator would partially unify expressions even if they were not monads. This could be taken advantage of to propagate information that could help elaboration make progress, for example the first `change` worked because the monad lift coercion elaborator was unifying `@Eq _ _` with `@Eq (Nat × Nat) p`. As such, this is a breaking change; you may need to adjust expressions to include additional implicit arguments.", "pull request": "6024"}
{"Version": "v4.15.0", "section": "Language", "text": "adds a normalization rule to `bv_normalize` (which is used by `bv_decide`) that converts `x / 2^k` into `x >>> k` under suitable conditions, allowing cheaper shifting circuits instead of expensive division circuits.", "pull request": "6029"}
{"Version": "v4.15.0", "section": "Language", "text": "fixes `simp only [· ∈ ·]` after #5020.", "pull request": "6030"}
{"Version": "v4.15.0", "section": "Language", "text": "introduces the and flattening pre processing pass from Bitwuzla to `bv_decide`. It splits hypotheses of the form `(a && b) = true` into `a = true` and `b = true` which synergizes with the existing embedded constraint substitution pass.", "pull request": "6035"}
{"Version": "v4.15.0", "section": "Language", "text": "fixes `bv_decide`'s embedded constraint substitution to generate correct counter examples in the corner case where duplicate theorems are in the local context.", "pull request": "6037"}
{"Version": "v4.15.0", "section": "Language", "text": "add `LEAN_ALWAYS_INLINE` to some functions", "pull request": "6045"}
{"Version": "v4.15.0", "section": "Language", "text": "fixes `simp?` suggesting output with invalid indentation", "pull request": "6048"}
{"Version": "v4.15.0", "section": "Language", "text": "mark `Meta.Context.config` as private", "pull request": "6051"}
{"Version": "v4.15.0", "section": "Language", "text": "fixes the caching infrastructure for `whnf` and `isDefEq`, ensuring the cache accounts for all relevant configuration flags. Cleans up `WHNF.lean` and improves `whnf` configuration.", "pull request": "6053"}
{"Version": "v4.15.0", "section": "Language", "text": "adds a simp_arith benchmark.", "pull request": "6061"}
{"Version": "v4.15.0", "section": "Language", "text": "optimize Nat.Linear.Expr.toPoly", "pull request": "6062"}
{"Version": "v4.15.0", "section": "Language", "text": "optimize Nat.Linear.Poly.norm", "pull request": "6064"}
{"Version": "v4.15.0", "section": "Language", "text": "improves the asymptotic performance of `simp_arith` when there are many variables to consider.", "pull request": "6068"}
{"Version": "v4.15.0", "section": "Language", "text": "adds options to `bv_decide`'s configuration so that all non mandatory preprocessing passes can be disabled.", "pull request": "6077"}
{"Version": "v4.15.0", "section": "Language", "text": "changes how the canonicalizer handles `forall` and `lambda`, replacing bvars with temporary fvars. Fixes a bug reported by @hrmacbeth on zulip about quantifiers in CanonM.", "pull request": "6082"}
{"Version": "v4.15.0", "section": "Language", "text": "use mkFreshUserName in ArgsPacker", "pull request": "6093"}
{"Version": "v4.15.0", "section": "Language", "text": "improves the `#print` command for structures to show all fields and which parents the fields were inherited from, hiding internal details such as which parents are represented as subobjects. The pretty printer for private constants is also improved. Private names from the current module are handled like other names; private names from other modules are hygienic.", "pull request": "6096"}
{"Version": "v4.15.0", "section": "Language", "text": "modifies the signature of `Nat.fold`, `Nat.foldRev`, `Nat.any`, `Nat.all`, so that the function is passed the upper bound, enabling compile time checks instead of runtime checks.", "pull request": "6139"}
{"Version": "v4.15.0", "section": "Language", "text": "adds a primitive for creating temporary directories, akin to the existing functionality for creating temporary files.", "pull request": "6148"}
{"Version": "v4.15.0", "section": "Language", "text": "completes the elementwise accessors for `ofNatLt`, `allOnes`, and `not` by adding their implementations of `getMsbD`.", "pull request": "6149"}
{"Version": "v4.15.0", "section": "Language", "text": "completes the `toInt` interface for `BitVec` bitwise operations.", "pull request": "6151"}
{"Version": "v4.15.0", "section": "Language", "text": "implements `BitVec.toInt_abs`.", "pull request": "6154"}
{"Version": "v4.15.0", "section": "Language", "text": "adds `toNat` theorems for `BitVec.signExtend.`", "pull request": "6155"}
{"Version": "v4.15.0", "section": "Language", "text": "adds toInt theorems for BitVec.signExtend.", "pull request": "6157"}
{"Version": "v4.15.0", "section": "Language", "text": "adds theorem `mod_eq_sub`, makes theorem `sub_mul_eq_mod_of_lt_of_le` not private anymore and moves it within the `rotate*` section to use it in other proofs.", "pull request": "6160"}
{"Version": "v4.15.0", "section": "Language", "text": "uses `Array.findFinIdx?` in preference to `Array.findIdx?` where possible, converting runtime checks to compile time checks.", "pull request": "6184"}
{"Version": "v4.15.0", "section": "Language", "text": "completes the `toNat` theorems for bitwise operations (`and`, `or`, `xor`, `shiftLeft`, `shiftRight`) of the UInt types and adds `toBitVec` theorems as well; renames `and_toNat` to `toNat_and`.", "pull request": "6188"}
{"Version": "v4.15.0", "section": "Language", "text": "adds the builtin simproc `USize.reduceToNat` which reduces `USize.toNat` on literals less than `UInt32.size`.", "pull request": "6190"}
{"Version": "v4.15.0", "section": "Language", "text": "adds `Array.zipWithAll` and lemmas relating it to `List.zipWithAll`.", "pull request": "6191"}
{"Version": "v4.15.0", "section": "Language", "text": "adds deprecations for `Lean.HashMap` functions which did not receive deprecation attributes initially.", "pull request": "6192"}
{"Version": "v4.15.0", "section": "Language", "text": "completes the TODO in `Init.Data.Array.BinSearch`, removing `partial` and converting runtime checks to compile time checks.", "pull request": "6193"}
{"Version": "v4.15.0", "section": "Language", "text": "changes the signature of `Array.swap`, so it takes `Nat` with tactic-provided proofs of bounds. Renames `Array.swap!` to `Array.swapIfInBounds`.", "pull request": "6194"}
{"Version": "v4.15.0", "section": "Language", "text": "renames `Array.setD` to `Array.setIfInBounds`.", "pull request": "6195"}
{"Version": "v4.15.0", "section": "Language", "text": "upstreams the definition of `Vector` from Batteries, along with basic functions.", "pull request": "6197"}
{"Version": "v4.15.0", "section": "Language", "text": "upstreams `Nat.lt_pow_self` and `Nat.lt_two_pow` from Mathlib and uses them to prove the simp theorem `Nat.mod_two_pow`.", "pull request": "6200"}
{"Version": "v4.15.0", "section": "Language", "text": "makes `USize.toUInt64` a regular non-opaque definition.", "pull request": "6202"}
{"Version": "v4.15.0", "section": "Language", "text": "adds theorems `le_usize_size` and `usize_size_le`, simplifying inequalities about `USize.size`.", "pull request": "6203"}
{"Version": "v4.15.0", "section": "Language", "text": "upstreams some UInt theorems from Batteries and adds more `toNat`-related theorems. Also adds missing `UInt8` and `UInt16` to/from `USize` conversions.", "pull request": "6205"}
{"Version": "v4.15.0", "section": "Language", "text": "ensures `Fin.foldl` and `Fin.foldr` are semireducible so that certain defeqs (like `example (f : Fin 3 → ℕ) : List.ofFn f = [f 0, f 1, f 2] := rfl`) succeed.", "pull request": "6207"}
{"Version": "v4.15.0", "section": "Language", "text": "fix Vector.indexOf?", "pull request": "6208"}
{"Version": "v4.15.0", "section": "Language", "text": "adds `simp` lemmas about `List`'s `==` operation.", "pull request": "6217"}
{"Version": "v4.15.0", "section": "Language", "text": "fixes problems in non-Ubuntu Linux distributions for `tzdata` directory by providing a fallback, and trims unnecessary characters from local time identifier.", "pull request": "6221"}
{"Version": "v4.15.0", "section": "Language", "text": "changes the definition of `HashSet.insertMany` so it is equivalent to repeated `HashSet.insert`. Also clarifies docstrings of `insert` and `insertMany`.", "pull request": "6222"}
{"Version": "v4.15.0", "section": "Language", "text": "copies some lemmas about `List.foldX` to `Array`.", "pull request": "6230"}
{"Version": "v4.15.0", "section": "Language", "text": "upstreams lemmas about `Vector` from Batteries.", "pull request": "6233"}
{"Version": "v4.15.0", "section": "Language", "text": "upstreams the definition and lemmas about `List.finRange` from Batteries.", "pull request": "6234"}
{"Version": "v4.15.0", "section": "Language", "text": "relates `Nat.fold`/`foldRev`/`any`/`all` to corresponding list operations over `List.finRange`.", "pull request": "6235"}
{"Version": "v4.15.0", "section": "Language", "text": "refactors `Array.qsort` to remove runtime array checks and avoid `partial`. Uses `Vector` API with auto_params. Benchmarks show no regression.", "pull request": "6241"}
{"Version": "v4.15.0", "section": "Language", "text": "deprecates `Fin.ofNat` in favor of `Fin.ofNat'` which takes `[NeZero]` instead of returning `Fin (n+1)`.", "pull request": "6242"}
{"Version": "v4.15.0", "section": "Language", "text": "adds `numBits_pos`, `le_numBits`, `numBits_le` to simplify inequalities about `System.Platform.numBits`.", "pull request": "6247"}
{"Version": "v4.15.0", "section": "Compiler", "text": "changes `lean_sharecommon_{eq,hash}` to only consider the salient bytes of an object, not uninitialized capacity bytes.", "pull request": "5840"}
{"Version": "v4.15.0", "section": "Compiler", "text": "fixes a bug in the constant folding of `Nat.ble` and `Nat.blt` in the old code generator, preventing miscompilation.", "pull request": "6087"}
{"Version": "v4.15.0", "section": "Compiler", "text": "should make Lean better-behaved around sanitizers, addressing https://github.com/google/sanitizers/issues/1688. Taking the address of a local does not produce a monotonic measure of stack usage.", "pull request": "6143"}
{"Version": "v4.15.0", "section": "Compiler", "text": "fixes an issue where edits to a command containing a nested docstring fail to reparse the entire command.", "pull request": "6236"}
{"Version": "v4.15.0", "section": "Compiler", "text": "fixes `trace.profiler.pp` not using the term pretty printer.", "pull request": "6138"}
{"Version": "v4.15.0", "section": "Compiler", "text": "adds core metaprogramming functions for forking off background tasks from elaboration so that their results show up in reporting and the language server.", "pull request": "6170"}
{"Version": "v4.15.0", "section": "Compiler", "text": "fixes a bug with the `structure`/`class` command where parents not represented as subobjects but used other parents as instances caused a kernel error. Closes #2611.", "pull request": "6175"}
{"Version": "v4.15.0", "section": "Compiler", "text": "fixes a non-termination bug when generating match-expression equation theorems. The proof automation repeatedly applied `injection(` to the same local decl. See issue #6067.", "pull request": "6180"}
{"Version": "v4.15.0", "section": "Compiler", "text": "adds the builtin simproc `USize.reduceToNat` for `USize.toNat` on small literals. (Duplicate mention from above, but relevant to the code generator.)", "pull request": "6190"}
{"Version": "v4.15.0", "section": "Compiler", "text": "adds a primitive for accessing the current thread ID.", "pull request": "6049"}
{"Version": "v4.15.0", "section": "Compiler", "text": "fixes a bug in the proof assembly procedure used by the grind tactic (placeholder text).", "pull request": "6056"}
{"Version": "v4.15.0", "section": "Compiler", "text": "adds `Lean.loadPlugin` exposing functionality similar to `--plugin` to Lean code.", "pull request": "6130"}
{"Version": "v4.15.0", "section": "Pretty Printing", "text": "adds the option `pp.parens` (default: false) to eagerly insert parentheses, helpful for teaching and clarifying expression structure.", "pull request": "2934"}
{"Version": "v4.15.0", "section": "Pretty Printing", "text": "prevents `Nat.succ ?_` from pretty printing as `?_.succ`, improving `apply?` usability.", "pull request": "6014"}
{"Version": "v4.15.0", "section": "Pretty Printing", "text": "improves term info for coercions like `DFunLike.coe` so \"go to definition\" on the function name works. Also shows the coercee rather than the coercion expression on hover.", "pull request": "6085"}
{"Version": "v4.15.0", "section": "Pretty Printing", "text": "improves the `#print` command for structures to show all fields and their inheritance, hiding subobject parent details. Private constants pretty print better, handling current-module private names normally and others hygienically.", "pull request": "6096"}
{"Version": "v4.15.0", "section": "Pretty Printing", "text": "adds a new delab option `pp.coercions.types` which shows all coercions with an explicit type ascription when enabled.", "pull request": "6119"}
{"Version": "v4.15.0", "section": "Pretty Printing", "text": "ensures whitespace is printed before `+opt` and `-opt` config options, improving tactics like `simp?`.", "pull request": "6161"}
{"Version": "v4.15.0", "section": "Pretty Printing", "text": "fixes a bug where `#check ident` would ignore `pp.raw`. Closes #6090.", "pull request": "6181"}
{"Version": "v4.15.0", "section": "Pretty Printing", "text": "exposes the difference in \"synthesized type class instance is not definitionally equal\" errors.", "pull request": "6213"}
{"Version": "v4.15.0", "section": "Documentation", "text": "fixes a typo in the docstring for prec and improves the text slightly.", "pull request": "6009"}
{"Version": "v4.15.0", "section": "Documentation", "text": "join → flatten in docstring", "pull request": "6040"}
{"Version": "v4.15.0", "section": "Documentation", "text": "does some mild refactoring of the `Lean.Elab.StructInst` module while adding documentation.", "pull request": "6110"}
{"Version": "v4.15.0", "section": "Documentation", "text": "converts 3 doc-strings to module docs, presumably their intended usage.", "pull request": "6144"}
{"Version": "v4.15.0", "section": "Documentation", "text": "refine kernel code comments", "pull request": "6150"}
{"Version": "v4.15.0", "section": "Documentation", "text": "adjust file reference in Data.Sum", "pull request": "6158"}
{"Version": "v4.15.0", "section": "Documentation", "text": "explains the order in which `Expr.abstract` introduces de Bruijn indices.", "pull request": "6239"}
{"Version": "v4.15.0", "section": "Server", "text": "adds auto-completion for fields in structure instance notation. Querying completions in whitespace now shows the full list of fields. Custom syntax can enable this by wrapping its fields parser in `structInstFields`.", "pull request": "5835"}
{"Version": "v4.15.0", "section": "Server", "text": "fixes an old auto-completion bug where `x.` gave nonsensical completions if `x.` could not be elaborated as a dot completion.", "pull request": "5837"}
{"Version": "v4.15.0", "section": "Server", "text": "avoid max heartbeat error in completion", "pull request": "5996"}
{"Version": "v4.15.0", "section": "Server", "text": "fixes a regression with go-to-definition and doc highlight misbehaving on tactic blocks.", "pull request": "6031"}
{"Version": "v4.15.0", "section": "Server", "text": "fixes a performance issue where the Lean language server walked the full project file tree on every save, blocking all other requests and increasing latency.", "pull request": "6246"}
{"Version": "v4.15.0", "section": "Lake", "text": "update toolchain on `lake update`", "pull request": "5684"}
{"Version": "v4.15.0", "section": "Lake", "text": "adds a newline at end of each Lean file generated by `lake new` templates.", "pull request": "6026"}
{"Version": "v4.15.0", "section": "Lake", "text": "makes Lake no longer automatically fetch GitHub cloud releases if the package build directory is already present, preventing the cache from overwriting existing prebuilt artifacts unless manually fetched with `lake build <pkg>:release`.", "pull request": "6218"}
{"Version": "v4.15.0", "section": "Lake", "text": "makes `lake build` also print package materialization log lines eagerly. Previously only `lake update` did so.", "pull request": "6225"}
{"Version": "v4.15.0", "section": "Lake", "text": "improves errors when Lake fails to fetch from Reservoir, suggesting how to require it from GitHub if not indexed.", "pull request": "6231"}
{"Version": "v4.16.0", "section": "Language", "text": "makes all message constructors handle pretty printer errors.", "pull request": "3696"}
{"Version": "v4.16.0", "section": "Language", "text": "runs all linters for a single command (together) on a separate thread from further elaboration, making a first step towards parallelizing the elaborator.", "pull request": "4460"}
{"Version": "v4.16.0", "section": "Language", "text": "makes it harder to create \"fake\" theorems about definitions that are stubbed-out with sorry by ensuring that each sorry is not definitionally equal to any other. For example, this now fails:\nlean\nexample : (sorry : Nat) = sorry := rfl -- fails\n\nHowever, this still succeeds, since the sorry is a single indeterminate Nat:\nlean\ndef f (n : Nat) : Nat := sorry\nexample : f 0 = f 1 := rfl -- succeeds\n\nOne can be more careful by putting parameters to the right of the colon:\nlean\ndef f : (n : Nat) → Nat := sorry\nexample : f 0 = f 1 := rfl -- fails\n\nMost sources of synthetic sorries (recall: a sorry that originates from the elaborator) are now unique, except for elaboration errors, since making these unique tends to cause a confusing cascade of errors. In general, however, such sorries are labeled. This enables \"go to definition\" on sorry in the Infoview, which brings you to its origin. The option set_option pp.sorrySource true causes the pretty printer to show source position information on sorries.", "pull request": "5757"}
{"Version": "v4.16.0", "section": "Language", "text": "ensures that the configuration in Simp.Config is used when reducing terms and checking definitional equality in simp.", "pull request": "6123"}
{"Version": "v4.16.0", "section": "Language", "text": "lets _ be used in numeric literals as a separator. For example, 1_000_000, 0xff_ff or 0b_10_11_01_00. New lexical syntax:\ntext\nnumeral10 : [0-9]+ (\"_\"+ [0-9]+)*\nnumeral2  : \"0\" [bB] (\"_\"* [0-1]+)+\nnumeral8  : \"0\" [oO] (\"_\"* [0-7]+)+\nnumeral16 : \"0\" [xX] (\"_\"* hex_char+)+\nfloat     : numeral10 \".\" numeral10? [eE[+-]numeral10]", "pull request": "6204"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes a bug that could cause the injectivity tactic to fail in reducible mode, which could cause unfolding lemma generation to fail (used by tactics such as unfold). In particular, Lean.Meta.isConstructorApp'? was not aware that n + 1 is equivalent to Nat.succ n.", "pull request": "6270"}
{"Version": "v4.16.0", "section": "Language", "text": "modifies the \"foo has been deprecated: use betterFoo instead\" warning so that foo and betterFoo are hoverable.", "pull request": "6273"}
{"Version": "v4.16.0", "section": "Language", "text": "enables simp configuration options to be passed to norm_cast.", "pull request": "6278"}
{"Version": "v4.16.0", "section": "Language", "text": "ensure bv_decide uses definitional equality in its reflection procedure as much as possible. Previously it would build up explicit congruence proofs for the kernel to check. This reduces the size of proof terms passed to kernel speeds up checking of large reflection proofs.", "pull request": "6286"}
{"Version": "v4.16.0", "section": "Language", "text": "uses Lean.RArray in bv_decide's reflection proofs. Giving speedups on problems with lots of variables.", "pull request": "6288"}
{"Version": "v4.16.0", "section": "Language", "text": "sets up simprocs for all the remaining operations defined in Init.Data.Fin.Basic", "pull request": "6295"}
{"Version": "v4.16.0", "section": "Language", "text": "adds the debug.proofAsSorry option. When enabled, the proofs of theorems are ignored and replaced with sorry.", "pull request": "6300"}
{"Version": "v4.16.0", "section": "Language", "text": "removes unnecessary parameters from the funcion induction principles. This is a breaking change; broken code can typically be adjusted simply by passing fewer parameters.", "pull request": "6330"}
{"Version": "v4.16.0", "section": "Language", "text": "removes unnecessary parameters from the funcion induction principles. This is a breaking change; broken code can typically be adjusted simply by passing fewer parameters.", "pull request": "6330"}
{"Version": "v4.16.0", "section": "Language", "text": "adds the --error=kind option (shorthand: -Ekind) to the lean CLI. When set, messages of kind (e.g., linter.unusedVariables) will be reported as errors. This setting does nothing in interactive contexts (e.g., the server).", "pull request": "6362"}
{"Version": "v4.16.0", "section": "Language", "text": "adds support for Float32 and fixes a bug in the runtime.", "pull request": "6366"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes a bug in the simplifier. It was producing terms with loose bound variables when eliminating unused let_fun expressions.", "pull request": "6375"}
{"Version": "v4.16.0", "section": "Language", "text": "adds an explanation to the error message when cases and induction are applied to a term whose type is not an inductive type. For Prop, these tactics now suggest the by_cases tactic. Example:\ntactic 'cases' failed, major premise type is not an inductive type\n  Prop", "pull request": "6378"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes a bug in withTrackingZetaDelta and withTrackingZetaDeltaSet. The MetaM caches need to be reset. See new test.", "pull request": "6381"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes a bug in simp_all? that caused some local declarations to be omitted from the Try this: suggestions.", "pull request": "6385"}
{"Version": "v4.16.0", "section": "Language", "text": "ensures that revertAll clears auxiliary declarations when invoked directly by users.", "pull request": "6386"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes a type error in the proof generated by the contradiction tactic.", "pull request": "6387"}
{"Version": "v4.16.0", "section": "Language", "text": "ensures that simp and dsimp do not unfold definitions that are not intended to be unfolded by the user. See issue #5755 for an example affected by this issue.", "pull request": "6397"}
{"Version": "v4.16.0", "section": "Language", "text": "ensures Meta.check check projections.", "pull request": "6398"}
{"Version": "v4.16.0", "section": "Language", "text": "adds reserved names for congruence theorems used in the simplifier and grind tactics. The idea is prevent the same congruence theorems to be generated over and over again.", "pull request": "6412"}
{"Version": "v4.16.0", "section": "Language", "text": "introduces the following features to the WIP grind tactic:\n- Expr internalization.\n- Congruence theorem cache.\n- Procedure for adding new facts\n- New tracing options\n- New preprocessing steps: fold projections and eliminate dangling Expr.mdata", "pull request": "6413"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes a bug in Lean.Meta.Closure that would introduce under-applied delayed assignment metavariables, which would keep them from ever getting instantiated. This bug affected match elaboration when the expected type contained postponed elaboration problems, for example tactic blocks.", "pull request": "6414"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes multiple bugs in the WIP grind tactic. It also adds support for printing the grind internal state.", "pull request": "6419"}
{"Version": "v4.16.0", "section": "Language", "text": "adds a new preprocessing step to the grind tactic: universe-level normalization. The goal is to avoid missing equalities in the congruence closure module.", "pull request": "6428"}
{"Version": "v4.16.0", "section": "Language", "text": "adds the predicate Expr.fvarsSet a b, which returns true if and only if the free variables in a are a subset of the free variables in b.", "pull request": "6430"}
{"Version": "v4.16.0", "section": "Language", "text": "adds a custom type and instance canonicalizer for the (WIP) grind tactic. The grind tactic uses congruence closure but disregards types, type formers, instances, and proofs. Proofs are ignored due to proof irrelevance. Types, type formers, and instances are considered supporting elements and are not factored into congruence detection. Instead, grind only checks whether elements are structurally equal, which, in the context of the grind tactic, is equivalent to pointer equality. See new tests for examples where the canonicalizer is important.", "pull request": "6433"}
{"Version": "v4.16.0", "section": "Language", "text": "implements the congruence table for the (WIP) grind tactic. It also fixes several bugs, and adds a new preprocessing step.", "pull request": "6435"}
{"Version": "v4.16.0", "section": "Language", "text": "adds support for detecting congruent terms in the (WIP) grind tactic. It also introduces the grind.debug option, which, when set to true, checks many invariants after each equivalence class is merged. This option is intended solely for debugging purposes.", "pull request": "6437"}
{"Version": "v4.16.0", "section": "Language", "text": "ensures norm_cast doesn't fail to act in the presence of no_index annotations", "pull request": "6438"}
{"Version": "v4.16.0", "section": "Language", "text": "adds basic truth value propagation rules to the (WIP) grind tactic.", "pull request": "6441"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes the checkParents sanity check in grind.", "pull request": "6442"}
{"Version": "v4.16.0", "section": "Language", "text": "adds support for propagating the truth value of equalities in the (WIP) grind tactic.", "pull request": "6443"}
{"Version": "v4.16.0", "section": "Language", "text": "refactors grind and adds support for invoking the simplifier using the GrindM monad.", "pull request": "6447"}
{"Version": "v4.16.0", "section": "Language", "text": "declares the command builtin_grind_propagator for registering equation propagator for grind. It also declares the auxiliary the attribute.", "pull request": "6448"}
{"Version": "v4.16.0", "section": "Language", "text": "completes the implementation of the command builtin_grind_propagator.", "pull request": "6449"}
{"Version": "v4.16.0", "section": "Language", "text": "adds support for generating (small) proofs for any two expressions that belong to the same equivalence class in the grind tactic state.", "pull request": "6452"}
{"Version": "v4.16.0", "section": "Language", "text": "improves bv_decide's performance in the presence of large literals.", "pull request": "6453"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes a bug in the equality proof generator in the (WIP) grind tactic.", "pull request": "6455"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes another bug in the equality proof generator in the (WIP) grind tactic.", "pull request": "6456"}
{"Version": "v4.16.0", "section": "Language", "text": "adds support for generating congruence proofs for congruences detected by the grind tactic.", "pull request": "6457"}
{"Version": "v4.16.0", "section": "Language", "text": "adds support for compact congruence proofs in the (WIP) grind tactic. The mkCongrProof function now verifies whether the congruence proof can be constructed using only congr, congrFun, and congrArg, avoiding the need to generate the more complex hcongr auxiliary theorems.", "pull request": "6458"}
{"Version": "v4.16.0", "section": "Language", "text": "adds the (WIP) grind tactic. It currently generates a warning message to make it clear that the tactic is not ready for production.", "pull request": "6459"}
{"Version": "v4.16.0", "section": "Language", "text": "adds a new propagation rule for negation to the (WIP) grind tactic.", "pull request": "6461"}
{"Version": "v4.16.0", "section": "Language", "text": "adds support for constructors to the (WIP) grind tactic. When merging equivalence classes, grind checks for equalities between constructors. If they are distinct, it closes the goal; if they are the same, it applies injectivity.", "pull request": "6463"}
{"Version": "v4.16.0", "section": "Language", "text": "completes support for literal values in the (WIP) grind tactic. grind now closes the goal whenever it merges two equivalence classes with distinct literal values.", "pull request": "6464"}
{"Version": "v4.16.0", "section": "Language", "text": "adds support for projection functions to the (WIP) grind tactic.", "pull request": "6465"}
{"Version": "v4.16.0", "section": "Language", "text": "completes the implementation of addCongrTable in the (WIP) grind tactic. It also adds a new test to demonstrate why the extra check is needed. It also updates the field cgRoot (congruence root).", "pull request": "6466"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes issue #6467", "pull request": "6468"}
{"Version": "v4.16.0", "section": "Language", "text": "adds support code for implementing e-match in the (WIP) grind tactic.", "pull request": "6469"}
{"Version": "v4.16.0", "section": "Language", "text": "introduces a command for specifying patterns used in the heuristic instantiation of global theorems in the grind tactic. Note that this PR only adds the parser.", "pull request": "6470"}
{"Version": "v4.16.0", "section": "Language", "text": "implements the command grind_pattern. The new command allows users to associate patterns with theorems. These patterns are used for performing heuristic instantiation with e-matching. In the future, we will add the attributes @[grind_eq], @[grind_fwd], and @[grind_bwd] to compute the patterns automatically for theorems.", "pull request": "6472"}
{"Version": "v4.16.0", "section": "Language", "text": "adds a deriving handler for the ToExpr class. It can handle mutual and nested inductive types, however it falls back to creating partial instances in such cases. This is upstreamed from the Mathlib deriving handler written by @kmill, but has fixes to handle autoimplicit universe level variables.", "pull request": "6473"}
{"Version": "v4.16.0", "section": "Language", "text": "adds pattern validation to the grind_pattern command. The new checkCoverage function will also be used to implement the attributes @[grind_eq], @[grind_fwd], and @[grind_bwd].", "pull request": "6474"}
{"Version": "v4.16.0", "section": "Language", "text": "adds support for activating relevant theorems for the (WIP) grind tactic. We say a theorem is relevant to a grind goal if the symbols occurring in its patterns also occur in the goal.", "pull request": "6475"}
{"Version": "v4.16.0", "section": "Language", "text": "internalize nested ground patterns when activating ematch theorems in the (WIP) grind tactic.", "pull request": "6478"}
{"Version": "v4.16.0", "section": "Language", "text": "implements E-matching for the (WIP) grind tactic. We still need to finalize and internalize the new instances.", "pull request": "6481"}
{"Version": "v4.16.0", "section": "Language", "text": "addresses a few error messages where diffs weren't being exposed.", "pull request": "6484"}
{"Version": "v4.16.0", "section": "Language", "text": "implements Grind.EMatch.instantiateTheorem in the (WIP) grind tactic.", "pull request": "6485"}
{"Version": "v4.16.0", "section": "Language", "text": "adds source position information for structure parent projections, supporting \"go to definition\". Closes #3063.", "pull request": "6487"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes and refactors the E-matching module for the (WIP) grind tactic.", "pull request": "6488"}
{"Version": "v4.16.0", "section": "Language", "text": "adds basic configuration options for the grind tactic.", "pull request": "6490"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes a bug in the theorem instantiation procedure in the (WIP) grind tactic. For example, it was missing the following instance in one of the tests:", "pull request": "6492"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes another theorem instantiation bug in the grind tactic. It also moves new instances to be processed to Goal.", "pull request": "6497"}
{"Version": "v4.16.0", "section": "Language", "text": "adds support in the grind tactic for propagating dependent forall terms forall (h : p), q[h] where p is a proposition.", "pull request": "6498"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes the proof canonicalizer for grind.", "pull request": "6499"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes a bug in the markNestedProofs used in grind. See new test.", "pull request": "6500"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes a bug in the proof assembly procedure utilized by the grind tactic.", "pull request": "6502"}
{"Version": "v4.16.0", "section": "Language", "text": "adds a simple strategy to the (WIP) grind tactic. It just keeps internalizing new theorem instances found by E-matching. The simple strategy can solve examples such as:", "pull request": "6503"}
{"Version": "v4.16.0", "section": "Language", "text": "adds the monotonicity tactic, intended to be used inside the partial_fixpoint feature.", "pull request": "6506"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes a bug in the sanity checkers for the grind tactic. See the new test for an example of a case where it was panicking.", "pull request": "6508"}
{"Version": "v4.16.0", "section": "Language", "text": "fixes a bug in the congruence closure data structure used in the grind tactic. The new test includes an example that previously caused a panic. A similar panic was also occurring in the test grind_nested_proofs.lean.", "pull request": "6509"}
{"Version": "v4.16.0", "section": "Language", "text": "adds a custom congruence rule for equality in grind. The new rule takes into account that Eq is a symmetric relation. In the future, we will add support for arbitrary symmetric relations. The current rule is important for propagating disequalities effectively in grind.", "pull request": "6510"}
{"Version": "v4.16.0", "section": "Language", "text": "introduces support for user-defined fallback code in the grind tactic. The fallback code can be utilized to inspect the state of failing grind subgoals and/or invoke user-defined automation. Users can now write grind on_failure <code>, where <code> should have the type GoalM Unit. See the modified tests in this PR for examples.", "pull request": "6512"}
{"Version": "v4.16.0", "section": "Language", "text": "adds support for (dependent) if-then-else terms (i.e., ite and dite applications) in the grind tactic.", "pull request": "6513"}
{"Version": "v4.16.0", "section": "Language", "text": "enhances the assertion of new facts in grind by avoiding the creation of unnecessary metavariables.", "pull request": "6514"}
{"Version": "v4.16.0", "section": "Library", "text": "adds BitVec.[toInt|toFin]_concat and moves a couple of theorems into the concat section, as BitVec.msb_concat is needed for the toInt_concat proof.", "pull request": "6182"}
{"Version": "v4.16.0", "section": "Library", "text": "completes the toNat theorems for the bitwise operations (and, or, xor, shiftLeft, shiftRight) of the UInt types and adds toBitVec theorems as well. It also renames and_toNat to toNat_and to fit with the current naming convention.", "pull request": "6188"}
{"Version": "v4.16.0", "section": "Library", "text": "adds theorems characterizing the value of the unsigned shift right of a bitvector in terms of its 2s complement interpretation as an integer. Unsigned shift right by at least one bit makes the value of the bitvector less than or equal to 2^(w-1), makes the interpretation of the bitvector Int and Nat agree. In the case when n = 0, then the shift right value equals the integer interpretation.", "pull request": "6238"}
{"Version": "v4.16.0", "section": "Library", "text": "changes the implementation of HashMap.toList, so the ordering agrees with HashMap.toArray.", "pull request": "6244"}
{"Version": "v4.16.0", "section": "Library", "text": "introduces the basic theory of permutations of Arrays and proves Array.swap_perm.", "pull request": "6272"}
{"Version": "v4.16.0", "section": "Library", "text": "moves IO.Channel and IO.Mutex from Init to Std.Sync and renames them to Std.Channel and Std.Mutex.", "pull request": "6282"}
{"Version": "v4.16.0", "section": "Library", "text": "upstreams List.length_flatMap, countP_flatMap and count_flatMap from Mathlib. These were not possible to state before we upstreamed List.sum.", "pull request": "6294"}
{"Version": "v4.16.0", "section": "Library", "text": "adds protected to Fin.cast and BitVec.cast, to avoid confusion with _root_.cast. These should mostly be used via dot-notation in any case.", "pull request": "6315"}
{"Version": "v4.16.0", "section": "Library", "text": "adds lemmas simplifying for loops over Option into Option.pelim, giving parity with lemmas simplifying for loops of List into List.fold.", "pull request": "6316"}
{"Version": "v4.16.0", "section": "Library", "text": "completes the basic API for BitVec.ofBool.", "pull request": "6317"}
{"Version": "v4.16.0", "section": "Library", "text": "generalizes the universe level for Array.find?, by giving it a separate implementation from Array.findM?.", "pull request": "6318"}
{"Version": "v4.16.0", "section": "Library", "text": "adds GetElem lemmas for the basic Vector operations.", "pull request": "6324"}
{"Version": "v4.16.0", "section": "Library", "text": "generalizes the panic functions to a type of Sort u rather than Type u. This better supports universe polymorphic types and avoids confusing errors.", "pull request": "6333"}
{"Version": "v4.16.0", "section": "Library", "text": "adds Nat theorems for distributing >>> over bitwise operations, paralleling those of BitVec.", "pull request": "6334"}
{"Version": "v4.16.0", "section": "Library", "text": "adds BitVec.[toFin|getMsbD]_setWidth and [getMsb|msb]_signExtend as well as ofInt_toInt.", "pull request": "6338"}
{"Version": "v4.16.0", "section": "Library", "text": "generalizes DecidableRel to allow a heterogeneous relation.", "pull request": "6341"}
{"Version": "v4.16.0", "section": "Library", "text": "reproduces the API around List.any/all for Array.any/all.", "pull request": "6353"}
{"Version": "v4.16.0", "section": "Library", "text": "makes fixes suggested by the Batteries environment linters, particularly simpNF, and unusedHavesSuffices.", "pull request": "6364"}
{"Version": "v4.16.0", "section": "Library", "text": "expands the Array.set and Array.setIfInBounds lemmas to match existing lemmas for List.set.", "pull request": "6365"}
{"Version": "v4.16.0", "section": "Library", "text": "brings Vector lemmas about membership and indexing to parity with List and Array.", "pull request": "6367"}
{"Version": "v4.16.0", "section": "Library", "text": "adds lemmas about Vector.set, anyM, any, allM, and all.", "pull request": "6369"}
{"Version": "v4.16.0", "section": "Library", "text": "adds theorems about == on Vector, reproducing those already on List and Array.", "pull request": "6376"}
{"Version": "v4.16.0", "section": "Library", "text": "replaces the inductive predicate List.lt with an upstreamed version of List.Lex from Mathlib. (Previously Lex.lt was defined in terms of <; now it is generalized to take an arbitrary relation.) This subtly changes the notion of ordering on List α.\n\n  List.lt was a weaker relation: in particular if l₁ < l₂, then a :: l₁ < b :: l₂ may hold according to List.lt even if a and b are merely incomparable (either neither a < b nor b < a), whereas according to List.Lex this would require a = b.\n\n  When < is total, in the sense that ¬ · < · is antisymmetric, then the two relations coincide.\n\n  Mathlib was already overriding the order instances for List α, so this change should not be noticed by anyone already using Mathlib.\n\n  We simultaneously add the boolean valued List.lex function, parameterised by a BEq typeclass and an arbitrary lt function. This will support the flexibility previously provided for List.lt, via a == function which is weaker than strict equality.", "pull request": "6379"}
{"Version": "v4.16.0", "section": "Library", "text": "redefines Range.forIn' and Range.forM, in preparation for writing lemmas about them.", "pull request": "6390"}
{"Version": "v4.16.0", "section": "Library", "text": "requires that the step size in Std.Range is positive, to avoid ill-specified behaviour.", "pull request": "6391"}
{"Version": "v4.16.0", "section": "Library", "text": "adds lemmas reducing for loops over Std.Range to for loops over List.range'.", "pull request": "6396"}
{"Version": "v4.16.0", "section": "Library", "text": "adds basic lemmas about lexicographic order on Array and Vector, achieving parity with List.", "pull request": "6399"}
{"Version": "v4.16.0", "section": "Library", "text": "adds missing lemmas about lexicographic order on List/Array/Vector.", "pull request": "6423"}
{"Version": "v4.16.0", "section": "Library", "text": "adds the necessary domain theory that backs the partial_fixpoint feature.", "pull request": "6477"}
{"Version": "v4.16.0", "section": "Compiler", "text": "adds support for HEq to the new code generator.", "pull request": "6311"}
{"Version": "v4.16.0", "section": "Compiler", "text": "adds support for Float32 to the Lean runtime.", "pull request": "6348"}
{"Version": "v4.16.0", "section": "Compiler", "text": "adds missing features and fixes bugs in the Float32 support", "pull request": "6350"}
{"Version": "v4.16.0", "section": "Compiler", "text": "ensures the new code generator produces code for opaque definitions that are not tagged as @[extern].\nRemark: This is the behavior of the old code generator.", "pull request": "6383"}
{"Version": "v4.16.0", "section": "Compiler", "text": "adds support for erasure of Decidable.decide to the new code generator. It also adds a new Probe.runOnDeclsNamed function, which is helpful for writing targeted single-file tests of compiler internals.", "pull request": "6405"}
{"Version": "v4.16.0", "section": "Compiler", "text": "fixes a bug in the sharecommon module, which was returning incorrect results for objects that had already been processed by sharecommon. See the new test for an example that triggered the bug.", "pull request": "6415"}
{"Version": "v4.16.0", "section": "Compiler", "text": "adds support for extern LCNF decls, which is required for parity with the existing code generator.", "pull request": "6429"}
{"Version": "v4.16.0", "section": "Pretty Printing", "text": "adjusts the way the pretty printer unresolves names. It used to make use of all exports when pretty printing, but now it only uses exports that put names into parent namespaces (heuristic: these are \"API exports\" that are intended by the library author), rather than \"horizontal exports\" that put the names into an unrelated namespace, which the dot notation feature in #6189 now incentivizes.", "pull request": "5689"}
{"Version": "v4.16.0", "section": "Pretty Printing", "text": "makes it harder to create \"fake\" theorems about definitions that are stubbed-out with sorry by ensuring that each sorry is not definitionally equal to any other. For example, this now fails:\nlean\nexample : (sorry : Nat) = sorry := rfl -- fails\n\nHowever, this still succeeds, since the sorry is a single indeterminate Nat:\nlean\ndef f (n : Nat) : Nat := sorry\nexample : f 0 = f 1 := rfl -- succeeds\n\nOne can be more careful by putting parameters to the right of the colon:\nlean\ndef f : (n : Nat) → Nat := sorry\nexample : f 0 = f 1 := rfl -- fails\n\nMost sources of synthetic sorries (recall: a sorry that originates from the elaborator) are now unique, except for elaboration errors, since making these unique tends to cause a confusing cascade of errors. In general, however, such sorries are labeled. This enables \"go to definition\" on sorry in the Infoview, which brings you to its origin. The option set_option pp.sorrySource true causes the pretty printer to show source position information on sorries.", "pull request": "5757"}
{"Version": "v4.16.0", "section": "Documentation", "text": "adds a docstring to the @[app_delab] attribute.", "pull request": "6450"}
{"Version": "v4.16.0", "section": "Server", "text": "fixes a bug in structure instance field completion that caused it to not function correctly for bracketed structure instances written in Mathlib style.", "pull request": "6279"}
{"Version": "v4.16.0", "section": "Server", "text": "fixes a regression where goals that don't exist were being displayed. The regression was triggered by #5835 and originally caused by #4926.", "pull request": "6408"}
{"Version": "v4.16.0", "section": "Lake", "text": "changes Lake's build process to no longer use leanc for compiling C files or linking shared libraries and executables. Instead, it directly invokes the bundled compiler (or the native compiler if none) using the necessary flags.", "pull request": "6176"}
{"Version": "v4.16.0", "section": "Lake", "text": "adapts Lake modules to use prelude and includes them in the check-prelude CI.", "pull request": "6289"}
{"Version": "v4.16.0", "section": "Lake", "text": "ensures the the log error position is properly preserved when prepending stray log entries to the job log. It also adds comparison support for Log.Pos.", "pull request": "6291"}
{"Version": "v4.16.0", "section": "Lake", "text": "merges BuildJob and Job, deprecating the former. Job now contains a trace as part of its state which can be interacted with monadically. also simplifies the implementation of OpaqueJob.", "pull request": "6388"}
{"Version": "v4.16.0", "section": "Lake", "text": "adds the ability to override package entries in a Lake manifest via a separate JSON file. This file can be specified on the command line with --packages or applied persistently by placing it at .lake/package-overrides.json.", "pull request": "6411"}
{"Version": "v4.16.0", "section": "Lake", "text": "fixes a bug in #6388 where the Package.afterBuildCahe* functions would produce different traces depending on whether the cache was fetched.", "pull request": "6422"}
{"Version": "v4.16.0", "section": "Other", "text": "upstreams the ToLevel typeclass from mathlib and uses it to fix the existing ToExpr instances so that they are truly universe polymorphic (previously it generated malformed expressions when the universe level was nonzero). We improve on the mathlib definition of ToLevel to ensure the class always lives in Type, irrespective of the universe parameter.", "pull request": "6285"}
{"Version": "v4.16.0", "section": "Other", "text": "fixes errors at load time in the comparison mode of the Firefox profiler.", "pull request": "6363"}
{"Version": "v4.15.0", "section": "Language", "text": "implements `Simp.Config.implicitDefEqsProofs`. When `true` (default: `true`), `simp` will **not** create a proof term for a rewriting rule associated with an `rfl`-theorem. Rewriting rules are provided by users by annotating theorems with the attribute `@[simp]`. If the proof of the theorem is just `rfl` (reflexivity), and `implicitDefEqProofs := true`, `simp` will **not** create a proof term which is an application of the annotated theorem.", "pull request": "4595"}
{"Version": "v4.15.0", "section": "Language", "text": "avoid negative environment lookup", "pull request": "5429"}
{"Version": "v4.15.0", "section": "Language", "text": "ensure `instantiateMVarsProfiling` adds a trace node", "pull request": "5501"}
{"Version": "v4.15.0", "section": "Language", "text": "adds a feature to the the mutual def elaborator where the `instance` command yields theorems instead of definitions when the class is a `Prop`.", "pull request": "5856"}
{"Version": "v4.15.0", "section": "Language", "text": "unset trailing for `simpa?` \"try this\" suggestion", "pull request": "5907"}
{"Version": "v4.15.0", "section": "Language", "text": "changes the rule for which projections become instances. Before, all parents along with all indirect ancestors that were represented as subobject fields would have their projections become instances. Now only projections for direct parents become instances.", "pull request": "5920"}
{"Version": "v4.15.0", "section": "Language", "text": "make `all_goals` admit goals on failure", "pull request": "5934"}
{"Version": "v4.15.0", "section": "Language", "text": "introduce synthetic atoms in bv_decide", "pull request": "5942"}
{"Version": "v4.15.0", "section": "Language", "text": "adds a new definition `Message.kind` which returns the top-level tag of a message. This is serialized as the new field `kind` in `SerialMessaege` so that i can be used by external consumers (e.g., Lake) to identify messages via `lean --json`.", "pull request": "5945"}
{"Version": "v4.15.0", "section": "Language", "text": "`arg` conv tactic misreported number of arguments on error", "pull request": "5968"}
{"Version": "v4.15.0", "section": "Language", "text": "BitVec.twoPow in bv_decide", "pull request": "5979"}
{"Version": "v4.15.0", "section": "Language", "text": "simplifies the implementation of `omega`.", "pull request": "5991"}
{"Version": "v4.15.0", "section": "Language", "text": "fix style in bv_decide normalizer", "pull request": "5992"}
{"Version": "v4.15.0", "section": "Language", "text": "adds configuration options for `decide`/`decide!`/`native_decide` and refactors the tactics to be frontends to the same backend. Adds a `+revert` option that cleans up the local context and reverts all local variables the goal depends on, along with indirect propositional hypotheses. Makes `native_decide` fail at elaboration time on failure without sacrificing performance (the decision procedure is still evaluated just once). Now `native_decide` supports universe polymorphism.", "pull request": "5999"}
{"Version": "v4.15.0", "section": "Language", "text": "changes `bv_decide`'s configuration from lots of `set_option` to an elaborated config like `simp` or `omega`. The notable exception is `sat.solver` which is still a `set_option` such that users can configure a custom SAT solver globally for an entire project or file. Additionally it introduces the ability to set `maxSteps` for the simp preprocessing run through the new config.", "pull request": "6010"}
{"Version": "v4.15.0", "section": "Language", "text": "improves the validation of new syntactic tokens. Previously, the validation code had inconsistencies: some atoms would be accepted only if they had a leading space as a pretty printer hint. Additionally, atoms with internal whitespace are no longer allowed.", "pull request": "6012"}
{"Version": "v4.15.0", "section": "Language", "text": "removes the `decide!` tactic in favor of `decide +kernel` (breaking change).", "pull request": "6016"}
{"Version": "v4.15.0", "section": "Language", "text": "removes @[specilize] from `MkBinding.mkBinding`, which is a function that cannot be specialized (as none of its arguments are functions). As a result, the specializable function `Nat.foldRevM.loop` doesn't get specialized, which leads to worse performing code.", "pull request": "6019"}
{"Version": "v4.15.0", "section": "Language", "text": "makes the `change` tactic and conv tactic use the same elaboration strategy. It works uniformly for both the target and local hypotheses. Now `change` can assign metavariables, for example:\n```lean\nexample (x y z : Nat) : x + y = z := by\n  change ?a = _\n  let w := ?a\n  -- now `w : Nat := x + y`\n```", "pull request": "6022"}
{"Version": "v4.15.0", "section": "Language", "text": "fixes a bug where the monad lift coercion elaborator would partially unify expressions even if they were not monads. This could be taken advantage of to propagate information that could help elaboration make progress, for example the first `change` worked because the monad lift coercion elaborator was unifying `@Eq _ _` with `@Eq (Nat × Nat) p`:\n```lean\nexample (p : Nat × Nat) : p = p := by\n  change _ = ⟨_, _⟩ -- used to work (yielding `p = (p.fst, p.snd)`), now it doesn't\n  change ⟨_, _⟩ = _ -- never worked\n```\nAs such, this is a breaking change; you may need to adjust expressions to include additional implicit arguments.", "pull request": "6024"}
{"Version": "v4.15.0", "section": "Language", "text": "adds a normalization rule to `bv_normalize` (which is used by `bv_decide`) that converts `x / 2^k` into `x >>> k` under suitable conditions. This allows us to simplify the expensive division circuits that are used for bitblasting into much cheaper shifting circuits. Concretely, it allows for the following canonicalization:", "pull request": "6029"}
{"Version": "v4.15.0", "section": "Language", "text": "fixes `simp only [· ∈ ·]` after #5020.", "pull request": "6030"}
{"Version": "v4.15.0", "section": "Language", "text": "introduces the and flattening pre processing pass from Bitwuzla to `bv_decide`. It splits hypotheses of the form `(a && b) = true` into `a = true` and `b = true` which has synergy potential with the already existing embedded constraint substitution pass.", "pull request": "6035"}
{"Version": "v4.15.0", "section": "Language", "text": "fixes `bv_decide`'s embedded constraint substitution to generate correct counter examples in the corner case where duplicate theorems are in the local context.", "pull request": "6037"}
{"Version": "v4.15.0", "section": "Language", "text": "add `LEAN_ALWAYS_INLINE` to some functions", "pull request": "6045"}
{"Version": "v4.15.0", "section": "Language", "text": "fixes `simp?` suggesting output with invalid indentation", "pull request": "6048"}
{"Version": "v4.15.0", "section": "Language", "text": "mark `Meta.Context.config` as private", "pull request": "6051"}
{"Version": "v4.15.0", "section": "Language", "text": "fixes the caching infrastructure for `whnf` and `isDefEq`, ensuring the cache accounts for all relevant configuration flags. It also cleans up the `WHNF.lean` module and improves the configuration of `whnf`.", "pull request": "6053"}
{"Version": "v4.15.0", "section": "Language", "text": "adds a simp_arith benchmark.", "pull request": "6061"}
{"Version": "v4.15.0", "section": "Language", "text": "optimize Nat.Linear.Expr.toPoly", "pull request": "6062"}
{"Version": "v4.15.0", "section": "Language", "text": "optimize Nat.Linear.Poly.norm", "pull request": "6064"}
{"Version": "v4.15.0", "section": "Language", "text": "improves the asymptotic performance of `simp_arith` when there are many variables to consider.", "pull request": "6068"}
{"Version": "v4.15.0", "section": "Language", "text": "adds options to `bv_decide`'s configuration structure such that all non mandatory preprocessing passes can be disabled.", "pull request": "6077"}
{"Version": "v4.15.0", "section": "Language", "text": "changes how the canonicalizer handles `forall` and `lambda`, replacing bvars with temporary fvars. Fixes a bug reported by @hrmacbeth on [zulip](https://leanprover.zulipchat.com/#narrow/channel/270676-lean4/topic/Quantifiers.20in.20CanonM/near/482483448).", "pull request": "6082"}
{"Version": "v4.15.0", "section": "Language", "text": "use mkFreshUserName in ArgsPacker", "pull request": "6093"}
{"Version": "v4.15.0", "section": "Language", "text": "improves the `#print` command for structures to show all fields and which parents the fields were inherited from, hiding internal details such as which parents are represented as subobjects. This information is still present in the constructor if needed. The pretty printer for private constants is also improved, and it now handles private names from the current module like any other name; private names from other modules are made hygienic.", "pull request": "6096"}
{"Version": "v4.15.0", "section": "Language", "text": "modifies the signature of `Nat.fold`, `Nat.foldRev`, `Nat.any`, `Nat.all`, so that the function is passed the upper bound. This allows us to change runtime array bounds checks to compile time checks in many places.", "pull request": "6139"}
{"Version": "v4.15.0", "section": "Language", "text": "adds a primitive for creating temporary directories, akin to the existing functionality for creating temporary files.", "pull request": "6148"}
{"Version": "v4.15.0", "section": "Language", "text": "completes the elementwise accessors for `ofNatLt`, `allOnes`, and `not` by adding their implementations of `getMsbD`.", "pull request": "6149"}
{"Version": "v4.15.0", "section": "Language", "text": "completes the `toInt` interface for `BitVec` bitwise operations.", "pull request": "6151"}
{"Version": "v4.15.0", "section": "Language", "text": "implements `BitVec.toInt_abs`.", "pull request": "6154"}
{"Version": "v4.15.0", "section": "Language", "text": "adds `toNat` theorems for `BitVec.signExtend.`", "pull request": "6155"}
{"Version": "v4.15.0", "section": "Language", "text": "adds toInt theorems for BitVec.signExtend.", "pull request": "6157"}
{"Version": "v4.15.0", "section": "Language", "text": "adds theorem `mod_eq_sub`, makes theorem `sub_mul_eq_mod_of_lt_of_le` not private anymore and moves its location within the `rotate*` section to use it in other proofs.", "pull request": "6160"}
{"Version": "v4.15.0", "section": "Language", "text": "uses `Array.findFinIdx?` in preference to `Array.findIdx?` where it allows converting a runtime bounds check to a compile time bounds check.", "pull request": "6184"}
{"Version": "v4.15.0", "section": "Language", "text": "completes the `toNat` theorems for the bitwise operations (`and`, `or`, `xor`, `shiftLeft`, `shiftRight`) of the UInt types and adds `toBitVec` theorems as well. It also renames `and_toNat` to `toNat_and` to fit with the current naming convention.", "pull request": "6188"}
{"Version": "v4.15.0", "section": "Language", "text": "adds the builtin simproc `USize.reduceToNat` which reduces the `USize.toNat` operation on literals less than `UInt32.size` (i.e., `4294967296`).", "pull request": "6190"}
{"Version": "v4.15.0", "section": "Language", "text": "adds `Array.zipWithAll`, and the basic lemmas relating it to `List.zipWithAll`.", "pull request": "6191"}
{"Version": "v4.15.0", "section": "Language", "text": "adds deprecations for `Lean.HashMap` functions which did not receive deprecation attributes initially.", "pull request": "6192"}
{"Version": "v4.15.0", "section": "Language", "text": "completes the TODO in `Init.Data.Array.BinSearch`, removing the `partial` keyword and converting runtime array bounds checks to compile time bounds checks.", "pull request": "6193"}
{"Version": "v4.15.0", "section": "Language", "text": "changes the signature of `Array.swap`, so it takes `Nat` arguments with tactic provided bounds checking. It also renames `Array.swap!` to `Array.swapIfInBounds`.", "pull request": "6194"}
{"Version": "v4.15.0", "section": "Language", "text": "renames `Array.setD` to `Array.setIfInBounds`.", "pull request": "6195"}
{"Version": "v4.15.0", "section": "Language", "text": "upstreams the definition of `Vector` from Batteries, along with the basic functions.", "pull request": "6197"}
{"Version": "v4.15.0", "section": "Language", "text": "upstreams `Nat.lt_pow_self` and `Nat.lt_two_pow` from Mathlib and uses them to prove the simp theorem `Nat.mod_two_pow`.", "pull request": "6200"}
{"Version": "v4.15.0", "section": "Language", "text": "makes `USize.toUInt64` a regular non-opaque definition.", "pull request": "6202"}
{"Version": "v4.15.0", "section": "Language", "text": "adds theorems `le_usize_size`, `usize_size_le`, which make proving inequalities about `USize.size` easier.", "pull request": "6203"}
{"Version": "v4.15.0", "section": "Language", "text": "upstreams some UInt theorems from Batteries and adds more `toNat`-related theorems. It also adds the missing `UInt8` and `UInt16` to/from `USize` conversions so that the interface is uniform across the UInt types.", "pull request": "6205"}
{"Version": "v4.15.0", "section": "Language", "text": "ensures the `Fin.foldl` and `Fin.foldr` are semireducible. Without this the defeq `example (f : Fin 3 → ℕ) : List.ofFn f = [f 0, f 1, f 2] := rfl` was failing.", "pull request": "6207"}
{"Version": "v4.15.0", "section": "Language", "text": "fix Vector.indexOf?", "pull request": "6208"}
{"Version": "v4.15.0", "section": "Language", "text": "adds `simp` lemmas about `List`'s `==` operation.", "pull request": "6217"}
{"Version": "v4.15.0", "section": "Language", "text": "fixes:\n- Problems in other linux distributions that the default `tzdata` directory is not the same as previously defined by ensuring it with a fallback behavior when directory is missing.\n- Trim unnecessary characters from local time identifier.", "pull request": "6221"}
{"Version": "v4.15.0", "section": "Language", "text": "changes the definition of `HashSet.insertMany` and `HashSet.Raw.insertMany` so that it is equivalent to repeatedly calling `HashSet.insert`/`HashSet.Raw.insert`. It also clarifies the docstrings of all the `insert` and `insertMany` functions.", "pull request": "6222"}
{"Version": "v4.15.0", "section": "Language", "text": "copies some lemmas about `List.foldX` to `Array`.", "pull request": "6230"}
{"Version": "v4.15.0", "section": "Language", "text": "upstreams lemmas about `Vector` from Batteries.", "pull request": "6233"}
{"Version": "v4.15.0", "section": "Language", "text": "upstreams the definition and basic lemmas about `List.finRange` from Batteries.", "pull request": "6234"}
{"Version": "v4.15.0", "section": "Language", "text": "relates that operations `Nat.fold`/`foldRev`/`any`/`all` to the corresponding List operations over `List.finRange`.", "pull request": "6235"}
{"Version": "v4.15.0", "section": "Language", "text": "refactors `Array.qsort` to remove runtime array bounds checks, and avoids the use of `partial`. We use the `Vector` API, along with auto_params, to avoid having to write any proofs. The new code benchmarks indistinguishably from the old.", "pull request": "6241"}
{"Version": "v4.15.0", "section": "Language", "text": "deprecates `Fin.ofNat` in favour of `Fin.ofNat'` (which takes an `[NeZero]` instance, rather than returning an element of `Fin (n+1)`).", "pull request": "6242"}
{"Version": "v4.15.0", "section": "Language", "text": "adds the theorems `numBits_pos`, `le_numBits`, `numBits_le`, which make proving inequalities about `System.Platform.numBits` easier.", "pull request": "6247"}
{"Version": "v4.15.0", "section": "Compiler", "text": "changes `lean_sharecommon_{eq,hash}` to only consider the salient bytes of an object, and not any bytes of any unspecified/uninitialized unused capacity.", "pull request": "5840"}
{"Version": "v4.15.0", "section": "Compiler", "text": "fixes a bug in the constant folding for the `Nat.ble` and `Nat.blt` function in the old code generator, leading to a miscompilation.", "pull request": "6087"}
{"Version": "v4.15.0", "section": "Compiler", "text": "should make lean better-behaved around sanitizers, per https://github.com/google/sanitizers/issues/1688. As far as I can tell, https://github.com/google/sanitizers/wiki/AddressSanitizerUseAfterReturn#algorithm replaces local variables with heap allocations, and so taking the address of a local is not effective at producing a monotonic measure of stack usage.", "pull request": "6143"}
{"Version": "v4.15.0", "section": "Compiler", "text": "fixes a bug in the constant folding for the `Nat.ble` and `Nat.blt` function in the old code generator, leading to a miscompilation.", "pull request": "6087"}
{"Version": "v4.15.0", "section": "Compiler", "text": "fixes an issue where edits to a command containing a nested docstring fail to reparse the entire command.", "pull request": "6236"}
{"Version": "v4.15.0", "section": "Compiler", "text": "fixes `trace.profiler.pp` not using the term pretty printer.", "pull request": "6138"}
{"Version": "v4.15.0", "section": "Compiler", "text": "adds core metaprogramming functions for forking off background tasks from elaboration such that their results are visible to reporting and the language server.", "pull request": "6170"}
{"Version": "v4.15.0", "section": "Compiler", "text": "fixes a bug with the `structure`/`class` command where if there are parents that are not represented as subobjects but which used other parents as instances, then there would be a kernel error. Closes #2611.", "pull request": "6175"}
{"Version": "v4.15.0", "section": "Compiler", "text": "fixes a non-termination bug that occurred when generating the match-expression equation theorems. The bug was triggered when the proof automation for the equation theorem repeatedly applied `injection(` to the same local declaration, as it could not be removed due to forward dependencies. See issue #6067 for an example that reproduces this issue.", "pull request": "6180"}
{"Version": "v4.15.0", "section": "Compiler", "text": "adds the builtin simproc `USize.reduceToNat` which reduces the `USize.toNat` operation on literals less than `UInt32.size` (i.e., `4294967296`).", "pull request": "6190"}
{"Version": "v4.15.0", "section": "Compiler", "text": "adds a primitive for accessing the current thread ID.", "pull request": "6049"}
{"Version": "v4.15.0", "section": "Compiler", "text": "fixes a bug in the proof assembly procedure utilized by the grind tactic.", "pull request": "6056"}
{"Version": "v4.15.0", "section": "Compiler", "text": "adds `Lean.loadPlugin` which exposes functionality similar to the `lean` executable's `--plugin` option to Lean code.", "pull request": "6130"}
{"Version": "v4.15.0", "section": "Pretty Printing", "text": "adds the option `pp.parens` (default: false) that causes the pretty printer to eagerly insert parentheses, which can be useful for teaching and for understanding the structure of expressions. For example, it causes `p → q → r` to pretty print as `p → (q → r)`.", "pull request": "2934"}
{"Version": "v4.15.0", "section": "Pretty Printing", "text": "prevents `Nat.succ ?_` from pretty printing as `?_.succ`, which should make `apply?` be more usable.", "pull request": "6014"}
{"Version": "v4.15.0", "section": "Pretty Printing", "text": "improves the term info for coercions marked with `CoeFnType.coeFun` (such as `DFunLike.coe` in Mathlib), making \"go to definition\" on the function name work. Hovering over such a coerced function will show the coercee rather than the coercion expression. The coercion expression can still be seen by hovering over the whitespace in the function application.", "pull request": "6085"}
{"Version": "v4.15.0", "section": "Pretty Printing", "text": "improves the `#print` command for structures to show all fields and which parents the fields were inherited from, hiding internal details such as which parents are represented as subobjects. This information is still present in the constructor if needed. The pretty printer for private constants is also improved, and it now handles private names from the current module like any other name; private names from other modules are made hygienic.", "pull request": "6096"}
{"Version": "v4.15.0", "section": "Pretty Printing", "text": "adds a new delab option `pp.coercions.types` which, when enabled, will display all coercions with an explicit type ascription.", "pull request": "6119"}
{"Version": "v4.15.0", "section": "Pretty Printing", "text": "ensures whitespace is printed before `+opt` and `-opt` configuration options when pretty printing, improving the experience of tactics such as `simp?`.", "pull request": "6161"}
{"Version": "v4.15.0", "section": "Pretty Printing", "text": "fixes a bug where the signature pretty printer would ignore the current setting of `pp.raw`. This fixes an issue where `#check ident` would not heed `pp.raw`. Closes #6090.", "pull request": "6181"}
{"Version": "v4.15.0", "section": "Pretty Printing", "text": "exposes the difference in \"synthesized type class instance is not definitionally equal\" errors.", "pull request": "6213"}
{"Version": "v4.15.0", "section": "Documentation", "text": "fixes a typo in the docstring for prec and makes the text slightly more precise.", "pull request": "6009"}
{"Version": "v4.15.0", "section": "Documentation", "text": "join → flatten in docstring", "pull request": "6040"}
{"Version": "v4.15.0", "section": "Documentation", "text": "does some mild refactoring of the `Lean.Elab.StructInst` module while adding documentation.", "pull request": "6110"}
{"Version": "v4.15.0", "section": "Documentation", "text": "converts 3 doc-string to module docs since it seems that this is what they were intended to be!", "pull request": "6144"}
{"Version": "v4.15.0", "section": "Documentation", "text": "refine kernel code comments", "pull request": "6150"}
{"Version": "v4.15.0", "section": "Documentation", "text": "adjust file reference in Data.Sum", "pull request": "6158"}
{"Version": "v4.15.0", "section": "Documentation", "text": "explains the order in which `Expr.abstract` introduces de Bruijn indices.", "pull request": "6239"}
{"Version": "v4.15.0", "section": "Server", "text": "adds auto-completion for the fields of structure instance notation. Specifically, querying the completions via `Ctrl+Space` in the whitespace of a structure instance notation will now bring up the full list of fields. Whitespace structure completion can be enabled for custom syntax by wrapping the parser for the list of fields in a `structInstFields` parser.", "pull request": "5835"}
{"Version": "v4.15.0", "section": "Server", "text": "fixes an old auto-completion bug where `x.` would issue nonsensical completions when `x.` could not be elaborated as a dot completion.", "pull request": "5837"}
{"Version": "v4.15.0", "section": "Server", "text": "avoid max heartbeat error in completion", "pull request": "5996"}
{"Version": "v4.15.0", "section": "Server", "text": "fixes a regression with go-to-definition and document highlight misbehaving on tactic blocks.", "pull request": "6031"}
{"Version": "v4.15.0", "section": "Server", "text": "fixes a performance issue where the Lean language server would walk the full project file tree every time a file was saved, blocking the processing of all other requests and notifications and significantly increasing overall language server latency after saving.", "pull request": "6246"}
{"Version": "v4.15.0", "section": "Lake", "text": "update toolchain on `lake update`", "pull request": "5684"}
{"Version": "v4.15.0", "section": "Lake", "text": "adds a newline at end of each Lean file generated by `lake new` templates.", "pull request": "6026"}
{"Version": "v4.15.0", "section": "Lake", "text": "makes Lake no longer automatically fetch GitHub cloud releases if the package build directory is already present (mirroring the behavior of the Reservoir cache). This prevents the cache from clobbering existing prebuilt artifacts. Users can still manually fetch the cache and clobber the build directory by running `lake build <pkg>:release`.", "pull request": "6218"}
{"Version": "v4.15.0", "section": "Lake", "text": "makes `lake build` also eagerly print package materialization log lines. Previously, only a `lake update` performed eager logging.", "pull request": "6225"}
{"Version": "v4.15.0", "section": "Lake", "text": "improves the errors Lake produces when it fails to fetch a dependency from Reservoir. If the package is not indexed, it will produce a suggestion about how to require it from GitHub.", "pull request": "6231"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "improves universe level inference for the resulting type of an `inductive` or `structure.` Recall that a `Prop`-valued inductive type is a syntactic subsingleton if it has at most one constructor and all the arguments to the constructor are in `Prop`. Such types have large elimination, so they could be defined in `Type` or `Prop` without any trouble. The way inference has changed is that if a type is a syntactic subsingleton with exactly one constructor, and the constructor has at least one parameter/field, then the command will prefer creating a `Prop` instead of a `Type`. The upshot is that the `: Prop` in `structure S : Prop` is often no longer needed. (With @arthur-adjedj).", "pull request": "5517"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "the command can now define recursive inductive types:\n```lean\nstructure Tree where\n  n : Nat\n  children : Fin n → Tree\n\ndef Tree.size : Tree → Nat\n  | {n, children} => Id.run do\n    let mut s := 0\n    for h : i in [0 : n] do\n      s := s + (children ⟨i, h.2⟩).size\n    pure s\n```", "pull request": "5842"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a bug where Mathlib's `Type*` elaborator could lead to incorrect universe parameters with the command.", "pull request": "5814"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fix bugs in default value processing for structure instance notation (with @arthur-adjedj).", "pull request": "3152"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fix bugs in default value processing for structure instance notation (with @arthur-adjedj).", "pull request": "5844"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "promotes instance synthesis order calculation failure from a soft error to a hard error.", "pull request": "5399"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "deprecates `:=` variants of `inductive` and `structure` (see breaking changes).", "pull request": "5542"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "makes `@[elab_as_elim]` require at least one discriminant, since otherwise there is no advantage to this alternative elaborator.", "pull request": "5671"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "enables field notation in explicit mode. The syntax `@x.f` elaborates as `@S.f` with `x` supplied to the appropriate parameter.", "pull request": "5528"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "modifies the dot notation resolution algorithm so that it can apply `CoeFun` instances. For example, Mathlib has `Multiset.card : Multiset α →+ Nat`, and now with `m : Multiset α`, the notation `m.card` resolves to `⇑Multiset.card m`.", "pull request": "5692"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a bug where 'don't know how to synthesize implicit argument' errors might have the incorrect local context when the eta arguments feature is activated.", "pull request": "5658"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a bug where `..` ellipses in patterns made use of optparams and autoparams.", "pull request": "5933"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "makes dot notation for structures resolve using all ancestors. Adds a resolution order for generalized field notation. By default a relaxed version of the algorithm tolerates inconsistencies, but `set_option structure.strictResolutionOrder true` makes inconsistent parent orderings into warnings.", "pull request": "5770"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fixes functional induction principle generation to avoid over-eta-expanding in the preprocessing step.", "pull request": "5619"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fixes structural nested recursion so that it is not confused when a nested type appears first.", "pull request": "5766"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a bug in functional induction principle generation when there are `let` bindings.", "pull request": "5803"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "improves functional induction principle generation to unfold aux definitions more carefully.", "pull request": "5904"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "refactors code for `Predefinition.Structural`.", "pull request": "5850"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a bug in \"type mismatch\" errors that would structurally assign metavariables during the algorithm to expose differences.", "pull request": "5276"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "makes \"type mismatch\" errors add type ascriptions to expose differences for numeric literals.", "pull request": "5919"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "makes \"type mismatch\" errors expose differences in the bodies of functions and pi types.", "pull request": "5922"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "improves the error message for invalid induction alternative names in `match` expressions (@josojo).", "pull request": "5888"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "improves `calc` error messages.", "pull request": "5719"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "improve the `#eval` command and introduce new features such as hoverable output when a `ToExpr` instance exists, auto-derivation of `Repr` instances, a new option `eval.type`, more precise error messages about missing `ToExpr`/`Repr`/`ToString`, collecting log messages in `MetaM`/`CoreM`, and a fix for `let rec` usage.", "pull request": "5627"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "improve the `#eval` command and introduce new features such as hoverable output when a `ToExpr` instance exists, auto-derivation of `Repr` instances, a new option `eval.type`, more precise error messages about missing `ToExpr`/`Repr`/`ToString`, collecting log messages in `MetaM`/`CoreM`, and a fix for `let rec` usage.", "pull request": "5663"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "improves the error message when `partial` fails to prove a type is inhabited. Add delta deriving.", "pull request": "5780"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "gives `partial` inhabitation the ability to create local `Inhabited` instances from parameters.", "pull request": "5821"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "new tactic configuration syntax. For example `simp +contextual (maxSteps := 22)` instead of `simp (config := { contextual := true, maxSteps := 22})`. This affects core tactics and how authors can define tactic configuration syntaxes. (See breaking changes.)", "pull request": "5883"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "new tactic configuration syntax. For example `simp +contextual (maxSteps := 22)` instead of `simp (config := { contextual := true, maxSteps := 22})`. This affects core tactics and how authors can define tactic configuration syntaxes. (See breaking changes.)", "pull request": "5898"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "new tactic configuration syntax. For example `simp +contextual (maxSteps := 22)` instead of `simp (config := { contextual := true, maxSteps := 22})`. This affects core tactics and how authors can define tactic configuration syntaxes. (See breaking changes.)", "pull request": "5928"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "new tactic configuration syntax. For example `simp +contextual (maxSteps := 22)` instead of `simp (config := { contextual := true, maxSteps := 22})`. This affects core tactics and how authors can define tactic configuration syntaxes. (See breaking changes.)", "pull request": "5932"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fixes the simpproc for `Fin` literals to reduce more consistently.", "pull request": "5632"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a bug in `simpa ... using t` where metavariables in `t` were not properly accounted for, and improves the type mismatch error.", "pull request": "5648"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fixes the docstring of `simp!` to actually talk about `simp!`.", "pull request": "5838"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds support for `attribute [simp ←]` which adds the reverse of a theorem as a global simp theorem.", "pull request": "5870"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds `decide!` tactic for using kernel reduction. (Renamed to `decide +kernel` in a future release.)", "pull request": "5665"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds inequality regression tests to `bv_decide` (@alexkeizer).", "pull request": "5714"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds `bv_toNat` tag for `toNat_ofInt` (@bollu).", "pull request": "5608"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds support for `at` in `ac_nf` and uses it in `bv_normalize` (@tobiasgrosser).", "pull request": "5618"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds udiv support to `bv_decide`.", "pull request": "5628"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds auxiliary bitblasters for negation and subtraction.", "pull request": "5635"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds more `getLsbD` bitblaster theory.", "pull request": "5637"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds umod support to `bv_decide`.", "pull request": "5652"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds performance benchmark for modulo in `bv_decide`.", "pull request": "5653"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "reduces error on `bv_check` to warning.", "pull request": "5655"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds `~~~(-x)` support in `bv_decide`.", "pull request": "5670"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "disables `ac_nf` by default in `bv_decide`.", "pull request": "5673"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fixes context tracking in `bv_decide` counter example generation.", "pull request": "5675"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds an error when the LRAT proof is invalid in `bv_decide`.", "pull request": "5676"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "introduces uninterpreted symbols everywhere in `bv_decide`.", "pull request": "5781"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds `BitVec.sdiv` support to `bv_decide`.", "pull request": "5823"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds `BitVec.ofBool` support to `bv_decide`.", "pull request": "5852"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds `if` support to `bv_decide`.", "pull request": "5855"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds support for all the SMTLIB BitVec divison/remainder operations to `bv_decide`.", "pull request": "5869"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds embedded constraint substitution to `bv_decide`.", "pull request": "5886"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fixes loose mvars bug in `bv_normalize`.", "pull request": "5918"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "improves the `congr` conv tactic to handle over-applied functions.", "pull request": "5861"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "improves the `arg` conv tactic so it can access more arguments, handle over-applied functions, generate specialized congruence lemmas for the specific argument, apply to pi types, and adds negative indexing. Also shows intermediate states with `enter [...]`.", "pull request": "5894"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a bug where `generalize ... at *` would apply to implementation details. (@ymherklotz)", "pull request": "4846"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "upstreams the `classical` tactic combinator.", "pull request": "5730"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "improves the error message when trying to unfold a local hypothesis that is not a local definition.", "pull request": "5815"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "changes how `apply` and `simp` elaborate, making them not disable error recovery. Improves hovers and completions with elaboration errors.", "pull request": "5862"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "changes how `apply` and `simp` elaborate, making them not disable error recovery. Improves hovers and completions with elaboration errors.", "pull request": "5863"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds declaration ranges for delta-derived instances in deriving clauses.", "pull request": "5899"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "removes unused syntax in `deriving` clauses for providing arguments to deriving handlers (see breaking changes).", "pull request": "5265"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "upstreams and updates `#where`, a command that reports the current scope information.", "pull request": "5065"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "makes the unused variables linter ignore variables defined in tactics by default, avoiding performance bottlenecks.", "pull request": "5338"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "ensures that linters do not run on `#guard_msgs` itself.", "pull request": "5644"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds `pushGoal`/`pushGoals` and `popGoal` for manipulating the goal state. Modifies `closeMainGoalUsing` to run callbacks in a context with the main goal removed, etc. Also modifies `withCollectingNewGoalsFrom` to take the `parentTag` explicitly. Modifies `elabTermWithHoles` to optionally take `parentTag?`.", "pull request": "5720"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fixes `getFunInfo` and `inferType` to use `withAtLeastTransparency` instead of `withTransparency`.", "pull request": "5563"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fixes `RecursorVal.getInduct` to return the name of major argument’s type, enabling structure eta for nested inductives.", "pull request": "5679"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "removes unused `mkRecursorInfoForKernelRec`.", "pull request": "5681"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "makes discrimination trees index the domains of foralls, improving performance of `simplify` and type class search.", "pull request": "5686"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds `Lean.Expr.name?` recognizer for `Name` expressions.", "pull request": "5760"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "modifies `liftCommandElabM` to preserve more state, fixing an issue where using it would drop messages.", "pull request": "5800"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "makes it possible to use dot notation in `m!` strings, for example `m!\"{.ofConstName n}\"`.", "pull request": "5857"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "records the complete list of `structure` parents in the `StructureInfo` environment extension.", "pull request": "5841"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "records the complete list of `structure` parents in the `StructureInfo` environment extension.", "pull request": "5853"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a bug introduced earlier where heartbeat exceptions were no longer handled properly. Now such exceptions are tagged with `runtime.maxHeartbeats` (@eric-wieser).", "pull request": "5566"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "modifies proof objects produced by `ac_nf0` and `simp_arith` so the kernel is less prone to reducing expensive atoms.", "pull request": "5708"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "adds a `#version` command that prints Lean's version information.", "pull request": "5768"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "fixes elaborator algorithms to match kernel algorithms for primitive projections (`Expr.proj`).", "pull request": "5822"}
{"Version": "v4.14.0", "section": "Language features, tactics, and metaprograms", "text": "improves the docstring for the `rwa` tactic.", "pull request": "5811"}
{"Version": "v4.14.0", "section": "Language server, widgets, and IDE extensions", "text": "fixes `WorkspaceClientCapabilities` to make `applyEdit` optional, matching the LSP specification (@pzread).", "pull request": "5224"}
{"Version": "v4.14.0", "section": "Language server, widgets, and IDE extensions", "text": "fixes a server deadlock when shutting down the language server and a desync between client and language server after a file worker crash.", "pull request": "5340"}
{"Version": "v4.14.0", "section": "Language server, widgets, and IDE extensions", "text": "makes `initialize` and `builtin_initialize` participate in call hierarchy and other requests.", "pull request": "5560"}
{"Version": "v4.14.0", "section": "Language server, widgets, and IDE extensions", "text": "makes references in attributes participate in call hierarchy and other requests.", "pull request": "5650"}
{"Version": "v4.14.0", "section": "Language server, widgets, and IDE extensions", "text": "add auto-completion in tactic blocks without needing to type the first character of the tactic, and add tactic completion docs to tactic auto-completion items.", "pull request": "5666"}
{"Version": "v4.14.0", "section": "Language server, widgets, and IDE extensions", "text": "fixes several cases where goal states were not displayed in certain text cursor positions.", "pull request": "5677"}
{"Version": "v4.14.0", "section": "Language server, widgets, and IDE extensions", "text": "indicates deprecations in auto-completion items.", "pull request": "5707"}
{"Version": "v4.14.0", "section": "Language server, widgets, and IDE extensions", "text": "fix various performance issues in the language server.", "pull request": "5736"}
{"Version": "v4.14.0", "section": "Language server, widgets, and IDE extensions", "text": "fix various performance issues in the language server.", "pull request": "5752"}
{"Version": "v4.14.0", "section": "Language server, widgets, and IDE extensions", "text": "fix various performance issues in the language server.", "pull request": "5763"}
{"Version": "v4.14.0", "section": "Language server, widgets, and IDE extensions", "text": "fix various performance issues in the language server.", "pull request": "5802"}
{"Version": "v4.14.0", "section": "Language server, widgets, and IDE extensions", "text": "fix various performance issues in the language server.", "pull request": "5805"}
{"Version": "v4.14.0", "section": "Language server, widgets, and IDE extensions", "text": "distinguishes theorem auto-completions from non-theorem auto-completions.", "pull request": "5801"}
{"Version": "v4.14.0", "section": "Pretty printing", "text": "fixes a bug where goal states in messages might print newlines as spaces.", "pull request": "5640"}
{"Version": "v4.14.0", "section": "Pretty printing", "text": "adds option `pp.mvars.delayed` (default false) which when false causes delayed assignment metavariables to pretty print with what they are assigned to, rather than something like `?m.7 x`.", "pull request": "5643"}
{"Version": "v4.14.0", "section": "Pretty printing", "text": "adds options `pp.mvars.anonymous` and `pp.mvars.levels` which when false cause expression or level metavariables to print as `?_`.", "pull request": "5711"}
{"Version": "v4.14.0", "section": "Pretty printing", "text": "adjusts the `⋯` elaboration warning to mention `pp.maxSteps`.", "pull request": "5710"}
{"Version": "v4.14.0", "section": "Pretty printing", "text": "fixes the app unexpander for `sorryAx`.", "pull request": "5759"}
{"Version": "v4.14.0", "section": "Pretty printing", "text": "improves accuracy of binder names in the signature printer (e.g. for `#check`). Also fixes issues with consecutive hygienic names printing without a space, now `(x✝ y✝ : Nat)` instead of `(x✝y✝ : Nat)`.", "pull request": "5827"}
{"Version": "v4.14.0", "section": "Pretty printing", "text": "makes sure core delaborators respect `pp.explicit` when appropriate.", "pull request": "5830"}
{"Version": "v4.14.0", "section": "Pretty printing", "text": "makes sure name literals use escaping when pretty printing.", "pull request": "5639"}
{"Version": "v4.14.0", "section": "Pretty printing", "text": "adds delaborators for `<|>`, `<*>`, `>>`, `<*`, and `*>`.", "pull request": "5854"}
{"Version": "v4.14.0", "section": "Library", "text": "deprecates `Array.data`.", "pull request": "5687"}
{"Version": "v4.14.0", "section": "Library", "text": "uses a better default value for `Array.swapAt!`.", "pull request": "5705"}
{"Version": "v4.14.0", "section": "Library", "text": "moves `Array.mapIdx` lemmas to a new file.", "pull request": "5748"}
{"Version": "v4.14.0", "section": "Library", "text": "simplifies signature of `Array.mapIdx`.", "pull request": "5749"}
{"Version": "v4.14.0", "section": "Library", "text": "upstreams `Array.reduceOption`.", "pull request": "5758"}
{"Version": "v4.14.0", "section": "Library", "text": "adds simp lemmas for `Array.isEqv` and `BEq`.", "pull request": "5786"}
{"Version": "v4.14.0", "section": "Library", "text": "renames `Array.shrink` to `Array.take`, and relates it to `List.take`.", "pull request": "5796"}
{"Version": "v4.14.0", "section": "Library", "text": "upstreams `List.modify`, adds lemmas, and relates to `Array.modify`.", "pull request": "5798"}
{"Version": "v4.14.0", "section": "Library", "text": "relates `Array.forIn` and `List.forIn`.", "pull request": "5799"}
{"Version": "v4.14.0", "section": "Library", "text": "adds `Array.forIn'`, relating it to `List`.", "pull request": "5833"}
{"Version": "v4.14.0", "section": "Library", "text": "fixes deprecations in `Init.Data.Array.Basic` to not recommend a deprecated constant.", "pull request": "5848"}
{"Version": "v4.14.0", "section": "Library", "text": "adds `LawfulBEq (Array α) ↔ LawfulBEq α`.", "pull request": "5895"}
{"Version": "v4.14.0", "section": "Library", "text": "moves `@[simp]` from `back_eq_back?` to `back_push`.", "pull request": "5896"}
{"Version": "v4.14.0", "section": "Library", "text": "renames `Array.back` to `back!`.", "pull request": "5897"}
{"Version": "v4.14.0", "section": "Library", "text": "removes `List.redLength`.", "pull request": "5605"}
{"Version": "v4.14.0", "section": "Library", "text": "upstreams `List.mapIdx` and adds lemmas.", "pull request": "5696"}
{"Version": "v4.14.0", "section": "Library", "text": "upstreams `List.foldxM_map`.", "pull request": "5697"}
{"Version": "v4.14.0", "section": "Library", "text": "renames `List.join` to `List.flatten`.", "pull request": "5701"}
{"Version": "v4.14.0", "section": "Library", "text": "upstreams `List.sum`.", "pull request": "5703"}
{"Version": "v4.14.0", "section": "Library", "text": "marks `prefix_append_right_inj` as a simp lemma.", "pull request": "5706"}
{"Version": "v4.14.0", "section": "Library", "text": "fixes `List.drop_drop` addition order.", "pull request": "5716"}
{"Version": "v4.14.0", "section": "Library", "text": "renames `List.bind` and `Array.concatMap` to `flatMap`.", "pull request": "5731"}
{"Version": "v4.14.0", "section": "Library", "text": "renames `List.pure` to `List.singleton`.", "pull request": "5732"}
{"Version": "v4.14.0", "section": "Library", "text": "upstreams `ne_of_mem_of_not_mem`.", "pull request": "5742"}
{"Version": "v4.14.0", "section": "Library", "text": "upstreams `ne_of_apply_ne`.", "pull request": "5743"}
{"Version": "v4.14.0", "section": "Library", "text": "adds more `List.modify` lemmas.", "pull request": "5816"}
{"Version": "v4.14.0", "section": "Library", "text": "renames `List.groupBy` to `splitBy`.", "pull request": "5879"}
{"Version": "v4.14.0", "section": "Library", "text": "relates `for` loops over `List` with `foldlM`.", "pull request": "5913"}
{"Version": "v4.14.0", "section": "Library", "text": "removes `instBEqNat` which was not defeq to `instBEqOfDecidableEq`.", "pull request": "5694"}
{"Version": "v4.14.0", "section": "Library", "text": "deprecates `Nat.sum`.", "pull request": "5746"}
{"Version": "v4.14.0", "section": "Library", "text": "adds `Nat.forall_lt_succ` and variants.", "pull request": "5785"}
{"Version": "v4.14.0", "section": "Library", "text": "redefines unsigned fixed width integers in terms of `BitVec`.", "pull request": "5323"}
{"Version": "v4.14.0", "section": "Library", "text": "adds `UIntX.[val_ofNat, toBitVec_ofNat]`.", "pull request": "5735"}
{"Version": "v4.14.0", "section": "Library", "text": "defines `Int8`.", "pull request": "5790"}
{"Version": "v4.14.0", "section": "Library", "text": "removes native code for `UInt8.modn`.", "pull request": "5901"}
{"Version": "v4.14.0", "section": "Library", "text": "completes `BitVec.[getMsbD|getLsbD|msb]` for shifts.", "pull request": "5604"}
{"Version": "v4.14.0", "section": "Library", "text": "adds lemmas for division when denominator is zero.", "pull request": "5609"}
{"Version": "v4.14.0", "section": "Library", "text": "documents Bitblasting.", "pull request": "5620"}
{"Version": "v4.14.0", "section": "Library", "text": "moves `BitVec.udiv/umod/sdiv/smod` after `add/sub/mul/lt`.", "pull request": "5623"}
{"Version": "v4.14.0", "section": "Library", "text": "defines `udiv` normal form to be `/`, resp. `umod` and `%`.", "pull request": "5645"}
{"Version": "v4.14.0", "section": "Library", "text": "adds lemmas about arithmetic inequalities.", "pull request": "5646"}
{"Version": "v4.14.0", "section": "Library", "text": "expands relationship with `toFin`.", "pull request": "5680"}
{"Version": "v4.14.0", "section": "Library", "text": "adds `(getMSbD, msb)_(add, sub)` and `getLsbD_sub`.", "pull request": "5691"}
{"Version": "v4.14.0", "section": "Library", "text": "adds `udiv|umod_[zero|one|self]`.", "pull request": "5712"}
{"Version": "v4.14.0", "section": "Library", "text": "adds `sdiv_[zero|one|self]`.", "pull request": "5718"}
{"Version": "v4.14.0", "section": "Library", "text": "adds `(msb, getMsbD, getLsbD)_(neg, abs)`.", "pull request": "5721"}
{"Version": "v4.14.0", "section": "Library", "text": "adds `BitVec.toInt_sub`, simplifies `BitVec.toInt_neg`.", "pull request": "5772"}
{"Version": "v4.14.0", "section": "Library", "text": "proves that `intMin` is the smallest signed bitvector.", "pull request": "5778"}
{"Version": "v4.14.0", "section": "Library", "text": "adds `(msb, getMsbD)_twoPow`.", "pull request": "5851"}
{"Version": "v4.14.0", "section": "Library", "text": "adds `BitVec.[zero_ushiftRight|zero_sshiftRight|zero_mul]` and cleans up BVDecide.", "pull request": "5858"}
{"Version": "v4.14.0", "section": "Library", "text": "adds `(msb, getMsbD)_concat`.", "pull request": "5865"}
{"Version": "v4.14.0", "section": "Library", "text": "adds `Hashable (BitVec n)`.", "pull request": "5881"}
{"Version": "v4.14.0", "section": "Library", "text": "upstreams `String.dropPrefix?`.", "pull request": "5728"}
{"Version": "v4.14.0", "section": "Library", "text": "changes `String.dropPrefix?` signature.", "pull request": "5745"}
{"Version": "v4.14.0", "section": "Library", "text": "adds `Hashable Char` instance.", "pull request": "5747"}
{"Version": "v4.14.0", "section": "Library", "text": "adds interim implementation of `HashMap.modify`/`alter`.", "pull request": "5880"}
{"Version": "v4.14.0", "section": "Library", "text": "removes `@[simp]` from `Option.isSome_eq_isSome`.", "pull request": "5704"}
{"Version": "v4.14.0", "section": "Library", "text": "upstreams material on `Prod`.", "pull request": "5739"}
{"Version": "v4.14.0", "section": "Library", "text": "moves `Antisymm` to `Std.Antisymm`.", "pull request": "5740"}
{"Version": "v4.14.0", "section": "Library", "text": "upstreams basic material on `Sum`.", "pull request": "5741"}
{"Version": "v4.14.0", "section": "Library", "text": "adds `Nat.log2_two_pow` (@spinylobster).", "pull request": "5756"}
{"Version": "v4.14.0", "section": "Library", "text": "removes duplicated `ForIn` instances.", "pull request": "5892"}
{"Version": "v4.14.0", "section": "Library", "text": "removes `@[simp]` from `Sum.forall` and `Sum.exists`.", "pull request": "5900"}
{"Version": "v4.14.0", "section": "Library", "text": "removes redundant `Decidable` assumptions.", "pull request": "5812"}
{"Version": "v4.14.0", "section": "Compiler, runtime, and FFI", "text": "fixes help message flags, removes the `-f` flag and adds the `-g` flag.", "pull request": "5685"}
{"Version": "v4.14.0", "section": "Compiler, runtime, and FFI", "text": "adds `--short-version` (`-V`) option to display short version.", "pull request": "5930"}
{"Version": "v4.14.0", "section": "Compiler, runtime, and FFI", "text": "switches all 64-bit platforms over to consistently using GMP for bignum arithmetic.", "pull request": "5144"}
{"Version": "v4.14.0", "section": "Compiler, runtime, and FFI", "text": "raises the minimum supported Windows version to Windows 10 1903 (released May 2019).", "pull request": "5753"}
{"Version": "v4.14.0", "section": "Lake", "text": "changes `lake new math` to use `autoImplicit false`.", "pull request": "5715"}
{"Version": "v4.14.0", "section": "Lake", "text": "makes `Lake` not create core aliases in the `Lake` namespace.", "pull request": "5688"}
{"Version": "v4.14.0", "section": "Lake", "text": "adds a `text` option for `buildFile*` utilities.", "pull request": "5924"}
{"Version": "v4.14.0", "section": "Lake", "text": "makes `lake init` not `git init` when inside a git work tree.", "pull request": "5789"}
{"Version": "v4.14.0", "section": "Lake", "text": "has Lake update a package's `lean-toolchain` file on `lake update` if it finds the package's direct dependencies use a newer compatible toolchain, unless `--keep-toolchain` is used. (See breaking changes.)", "pull request": "5684"}
{"Version": "v4.14.0", "section": "Lake", "text": "makes Lake no longer automatically fetch GitHub cloud releases if the package build directory is already present. This prevents overwriting existing prebuilt artifacts unless the user manually fetches them with `lake build <pkg>:release`.", "pull request": "6218"}
{"Version": "v4.14.0", "section": "Lake", "text": "improves the errors Lake produces when it fails to fetch a dependency from Reservoir, providing suggestions about how to require it from GitHub if not indexed.", "pull request": "6231"}
{"Version": "v4.14.0", "section": "Documentation", "text": "fixes MSYS2 build instructions.", "pull request": "5617"}
{"Version": "v4.14.0", "section": "Documentation", "text": "points out that `OfScientific` is called with raw literals.", "pull request": "5725"}
{"Version": "v4.14.0", "section": "Documentation", "text": "adds a stub for application ellipsis notation.", "pull request": "5794"}
{"Version": "v4.14.0", "section": "Breaking changes", "text": "the syntax for providing arguments to deriving handlers has been removed. The minimum supported Windows version is now Windows 10 1903. The `--lean` CLI option for `lake` was removed. The old `inductive/structure/class ... :=` syntax is deprecated. Tactic configuration elaborators now land in TacticM. See details above.", "pull request": "5265"}
{"Version": "v4.14.0", "section": "Breaking changes", "text": "the syntax for providing arguments to deriving handlers has been removed. The minimum supported Windows version is now Windows 10 1903. The `--lean` CLI option for `lake` was removed. The old `inductive/structure/class ... :=` syntax is deprecated. Tactic configuration elaborators now land in TacticM. See details above.", "pull request": "5753"}
{"Version": "v4.14.0", "section": "Breaking changes", "text": "the syntax for providing arguments to deriving handlers has been removed. The minimum supported Windows version is now Windows 10 1903. The `--lean` CLI option for `lake` was removed. The old `inductive/structure/class ... :=` syntax is deprecated. Tactic configuration elaborators now land in TacticM. See details above.", "pull request": "5684"}
{"Version": "v4.14.0", "section": "Breaking changes", "text": "the syntax for providing arguments to deriving handlers has been removed. The minimum supported Windows version is now Windows 10 1903. The `--lean` CLI option for `lake` was removed. The old `inductive/structure/class ... :=` syntax is deprecated. Tactic configuration elaborators now land in TacticM. See details above.", "pull request": "5542"}
{"Version": "v4.14.0", "section": "Breaking changes", "text": "the syntax for providing arguments to deriving handlers has been removed. The minimum supported Windows version is now Windows 10 1903. The `--lean` CLI option for `lake` was removed. The old `inductive/structure/class ... :=` syntax is deprecated. Tactic configuration elaborators now land in TacticM. See details above.", "pull request": "5883"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "allows structure parents to be type synonyms.", "pull request": "5511"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "allows default values for structure fields to be noncomputable.", "pull request": "5531"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "improve the `rfl` tactic and give better error messages.", "pull request": "3714"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "improve the `rfl` tactic and give better error messages.", "pull request": "3718"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "makes `rfl` no longer use kernel defeq for ground terms.", "pull request": "3772"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "tags `Iff.refl` with `@[refl]` (@Parcly-Taxel).", "pull request": "5329"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "ensures that the `rfl` tactic tries `Iff.rfl` (@Parcly-Taxel).", "pull request": "5359"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "lets `unfold` do zeta-delta reduction of local definitions (like the Mathlib `unfold_let`).", "pull request": "4834"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "fixes spurious error in #5315 for `omega`.", "pull request": "5382"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "supports `Int.toNat` in `omega`.", "pull request": "5523"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "lets `simp` apply rules with higher-order patterns.", "pull request": "5479"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "fixes `induction`'s \"pre-tactic\" block indentation to avoid unintended usage.", "pull request": "5494"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "adds `ac_nf` tactic for normalizing expressions w.r.t. associativity and commutativity, tested on `BitVec` expressions.", "pull request": "5524"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "makes `extractLsb'` the primitive recognized by `bv_decide` instead of `extractLsb` (@alexkeizer).", "pull request": "5211"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "adds `bv_decide` diagnoses.", "pull request": "5365"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "adds normalization rules for `ofBool (a.getLsbD i)` and `ofBool a[i]` to `bv_decide` (@alexkeizer).", "pull request": "5375"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "enhances rewriting rules of `bv_decide`.", "pull request": "5423"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "presents the `bv_decide` counterexample at the API.", "pull request": "5433"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "handles `BitVec.ofNat` with `Nat` fvars in `bv_decide`.", "pull request": "5484"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "adds `bv_normalize` rules.", "pull request": "5506"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "adds `bv_normalize` rules.", "pull request": "5507"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "generalizes the `bv_normalize` pipeline to support more preprocessing passes.", "pull request": "5568"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "updates `bv_normalize` to current `BitVec` rewrites.", "pull request": "5573"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "bv_decide cleanups.", "pull request": "5408"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "bv_decide cleanups.", "pull request": "5493"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "bv_decide cleanups.", "pull request": "5578"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "preserve order of overapplied arguments in `elab_as_elim` procedure.", "pull request": "5266"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "generalizes `elab_as_elim` to allow arbitrary motive applications.", "pull request": "5510"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "refine how named arguments suppress explicit arguments. Breaking change: some omitted explicit args may need `_` now.", "pull request": "5283"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "refine how named arguments suppress explicit arguments. Breaking change: some omitted explicit args may need `_` now.", "pull request": "5512"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "modifies projection instance binder info so parameters that are instance-implicit in the type remain implicit.", "pull request": "5376"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "localizes universe metavariable errors to `let`-bindings and `fun` binders if possible, and prioritizes unsolved metavars over unsolved universes.", "pull request": "5402"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "must not reduce `ite` in the discriminant of a `match` when reducibility is `.reducible`.", "pull request": "5419"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "have autoparams report parameter/field on failure.", "pull request": "5474"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "makes automatic instance names about hygienic type names also be hygienic.", "pull request": "5530"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "makes `Repr` deriving instance handle explicit type parameters.", "pull request": "5432"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "functional induction: adds more equalities in context, more careful cleanup.", "pull request": "5364"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "fixes the unused variables linter complaining about match/tactic combos.", "pull request": "5335"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "fixes the unused variables linter complaining about wildcard patterns.", "pull request": "5337"}
{"Version": "v4.13.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a parse error when `..` is followed by a `.` on the next line.", "pull request": "4768"}
{"Version": "v4.13.0", "section": "Metaprogramming", "text": "handles level parameters in `Meta.evalExpr` (@eric-wieser).", "pull request": "3090"}
{"Version": "v4.13.0", "section": "Metaprogramming", "text": "instance for `Inhabited (TacticM α)` (@alexkeizer).", "pull request": "5401"}
{"Version": "v4.13.0", "section": "Metaprogramming", "text": "expose `Kernel.check` for debugging purposes.", "pull request": "5412"}
{"Version": "v4.13.0", "section": "Metaprogramming", "text": "improves the \"invalid projection\" type inference error in `inferType`.", "pull request": "5556"}
{"Version": "v4.13.0", "section": "Metaprogramming", "text": "allows `MVarId.assertHypotheses` to set `BinderInfo` and `LocalDeclKind`.", "pull request": "5587"}
{"Version": "v4.13.0", "section": "Metaprogramming", "text": "adds `MVarId.tryClearMany'`, a variant of `tryClearMany`.", "pull request": "5588"}
{"Version": "v4.13.0", "section": "Language server, widgets, and IDE extensions", "text": "decreases latency of auto-completion in tactic blocks.", "pull request": "5205"}
{"Version": "v4.13.0", "section": "Language server, widgets, and IDE extensions", "text": "fixes symbol occurrence highlighting in VS Code when moving cursor in from the right.", "pull request": "5237"}
{"Version": "v4.13.0", "section": "Language server, widgets, and IDE extensions", "text": "fixes several incorrect auto-completions being reported.", "pull request": "5257"}
{"Version": "v4.13.0", "section": "Language server, widgets, and IDE extensions", "text": "allows fallback to global auto-completions when context-specific completions fail.", "pull request": "5299"}
{"Version": "v4.13.0", "section": "Language server, widgets, and IDE extensions", "text": "fixes server break when changing whitespace after module header.", "pull request": "5312"}
{"Version": "v4.13.0", "section": "Language server, widgets, and IDE extensions", "text": "fixes auto-completion reporting non-existent namespaces.", "pull request": "5322"}
{"Version": "v4.13.0", "section": "Language server, widgets, and IDE extensions", "text": "always report some recent file range as progress while waiting for elaboration.", "pull request": "5428"}
{"Version": "v4.13.0", "section": "Pretty printing", "text": "make pretty printer escape identifiers that are tokens.", "pull request": "4979"}
{"Version": "v4.13.0", "section": "Pretty printing", "text": "makes formatter use the current token table.", "pull request": "5389"}
{"Version": "v4.13.0", "section": "Pretty printing", "text": "use breakable instead of unbreakable whitespace in token formatting.", "pull request": "5513"}
{"Version": "v4.13.0", "section": "Library", "text": "reduces allocations in `Json.compress`.", "pull request": "5222"}
{"Version": "v4.13.0", "section": "Library", "text": "upstreams `Zero` and `NeZero`.", "pull request": "5231"}
{"Version": "v4.13.0", "section": "Library", "text": "refactors `Lean.Elab.Deriving.FromToJson` (@arthur-adjedj).", "pull request": "5292"}
{"Version": "v4.13.0", "section": "Library", "text": "implements `Repr Empty` (@TomasPuverle).", "pull request": "5415"}
{"Version": "v4.13.0", "section": "Library", "text": "implements `To/FromJSON Empty` (@TomasPuverle).", "pull request": "5421"}
{"Version": "v4.13.0", "section": "Library", "text": "allows simplifying `dite_not`/`decide_not` with only `Decidable (¬p)`.", "pull request": "5263"}
{"Version": "v4.13.0", "section": "Library", "text": "fixes binders on `ite_eq_left_iff`.", "pull request": "5268"}
{"Version": "v4.13.0", "section": "Library", "text": "turns off `Inhabited (Sum α β)` instances.", "pull request": "5284"}
{"Version": "v4.13.0", "section": "Library", "text": "adds simp lemmas for `LawfulBEq`.", "pull request": "5355"}
{"Version": "v4.13.0", "section": "Library", "text": "adds `Nonempty` instances for products, letting more `partial` functions elaborate.", "pull request": "5374"}
{"Version": "v4.13.0", "section": "Library", "text": "updates Pi instance names.", "pull request": "5447"}
{"Version": "v4.13.0", "section": "Library", "text": "makes some instance arguments implicit.", "pull request": "5454"}
{"Version": "v4.13.0", "section": "Library", "text": "adds `heq_comm`.", "pull request": "5456"}
{"Version": "v4.13.0", "section": "Library", "text": "moves `@[simp]` from `exists_prop'` to `exists_prop`.", "pull request": "5529"}
{"Version": "v4.13.0", "section": "Library", "text": "fills gaps in `Bool` lemmas.", "pull request": "5228"}
{"Version": "v4.13.0", "section": "Library", "text": "adds notation `^^` for `Bool.xor`.", "pull request": "5332"}
{"Version": "v4.13.0", "section": "Library", "text": "removes `_root_.and` etc. and consistently uses `Bool.and`/`Bool.or`/`Bool.not`/`Bool.xor`.", "pull request": "5351"}
{"Version": "v4.13.0", "section": "Library", "text": "removes BitVec simps with complicated RHS.", "pull request": "5240"}
{"Version": "v4.13.0", "section": "Library", "text": "`BitVec.getElem_zeroExtend`.", "pull request": "5247"}
{"Version": "v4.13.0", "section": "Library", "text": "adds more simp lemmas for BitVec, improving confluence.", "pull request": "5248"}
{"Version": "v4.13.0", "section": "Library", "text": "removes `@[simp]` from some BitVec lemmas.", "pull request": "5249"}
{"Version": "v4.13.0", "section": "Library", "text": "changes `BitVec.intMin/Max` from abbrev to def.", "pull request": "5252"}
{"Version": "v4.13.0", "section": "Library", "text": "adds `BitVec.getElem_truncate` (@tobiasgrosser).", "pull request": "5278"}
{"Version": "v4.13.0", "section": "Library", "text": "adds udiv/umod bitblasting for `bv_decide` (@bollu).", "pull request": "5281"}
{"Version": "v4.13.0", "section": "Library", "text": "`BitVec` unsigned order theoretic results.", "pull request": "5297"}
{"Version": "v4.13.0", "section": "Library", "text": "adds more BitVec ordering theory for `UInt`.", "pull request": "5313"}
{"Version": "v4.13.0", "section": "Library", "text": "adds `toNat_sub_of_le` for BitVec (@bollu).", "pull request": "5314"}
{"Version": "v4.13.0", "section": "Library", "text": "adds `BitVec.truncate` lemmas.", "pull request": "5357"}
{"Version": "v4.13.0", "section": "Library", "text": "introduces `BitVec.setWidth` to unify zeroExtend and truncate (@tobiasgrosser).", "pull request": "5358"}
{"Version": "v4.13.0", "section": "Library", "text": "some BitVec GetElem lemmas.", "pull request": "5361"}
{"Version": "v4.13.0", "section": "Library", "text": "adds `BitVec.ofBool_[and|or|xor]_ofBool` theorems (@tobiasgrosser).", "pull request": "5385"}
{"Version": "v4.13.0", "section": "Library", "text": "more of `BitVec.getElem_*` (@tobiasgrosser).", "pull request": "5404"}
{"Version": "v4.13.0", "section": "Library", "text": "BitVec analogues of `Nat.mul_two` etc. (@bollu).", "pull request": "5410"}
{"Version": "v4.13.0", "section": "Library", "text": "`BitVec.toNat_{add,sub,mul_of_lt}` for non-overflow reasoning (@bollu).", "pull request": "5411"}
{"Version": "v4.13.0", "section": "Library", "text": "adds `_self`, `_zero`, `_allOnes` for `BitVec.[and|or|xor]` (@tobiasgrosser).", "pull request": "5413"}
{"Version": "v4.13.0", "section": "Library", "text": "adds `LawCommIdentity + IdempotentOp` for `BitVec.[and|or|xor]` (@tobiasgrosser).", "pull request": "5416"}
{"Version": "v4.13.0", "section": "Library", "text": "decidable quantifiers for BitVec.", "pull request": "5418"}
{"Version": "v4.13.0", "section": "Library", "text": "adds `BitVec.toInt_[intMin|neg|neg_of_ne_intMin]` (@tobiasgrosser).", "pull request": "5450"}
{"Version": "v4.13.0", "section": "Library", "text": "missing BitVec lemmas.", "pull request": "5459"}
{"Version": "v4.13.0", "section": "Library", "text": "adds `BitVec.[not_not, allOnes_shiftLeft_or_shiftLeft, allOnes_shiftLeft_and_shiftLeft]` (@luisacicolini).", "pull request": "5469"}
{"Version": "v4.13.0", "section": "Library", "text": "adds `BitVec.(shiftLeft_add_distrib, shiftLeft_ushiftRight)` (@luisacicolini).", "pull request": "5478"}
{"Version": "v4.13.0", "section": "Library", "text": "adds `sdiv_eq`/`smod_eq` for bitblasting in `bv_decide` (@bollu).", "pull request": "5487"}
{"Version": "v4.13.0", "section": "Library", "text": "adds `BitVec.toNat_[abs|sdiv|smod]` (@tobiasgrosser).", "pull request": "5491"}
{"Version": "v4.13.0", "section": "Library", "text": "`BitVec.(not_sshiftRight, not_sshiftRight_not, getMsb_not, msb_not)` (@luisacicolini).", "pull request": "5492"}
{"Version": "v4.13.0", "section": "Library", "text": "drop non-terminal simps in `BitVec.Lemmas` (@tobiasgrosser).", "pull request": "5499"}
{"Version": "v4.13.0", "section": "Library", "text": "unsimps `BitVec.divRec_succ'`.", "pull request": "5505"}
{"Version": "v4.13.0", "section": "Library", "text": "adds `BitVec.getElem_[add|add_add_bool|mul|rotateLeft|rotateRight…` (@tobiasgrosser).", "pull request": "5508"}
{"Version": "v4.13.0", "section": "Library", "text": "adds `BitVec.[add, sub, mul]_eq_xor` and `width_one_cases` (@luisacicolini).", "pull request": "5554"}
{"Version": "v4.13.0", "section": "Library", "text": "improve naming for `List.mergeSort` lemmas.", "pull request": "5242"}
{"Version": "v4.13.0", "section": "Library", "text": "provide `mergeSort` comparator autoParam.", "pull request": "5302"}
{"Version": "v4.13.0", "section": "Library", "text": "fix name of `List.length_mergeSort`.", "pull request": "5373"}
{"Version": "v4.13.0", "section": "Library", "text": "upstream `map_mergeSort`.", "pull request": "5377"}
{"Version": "v4.13.0", "section": "Library", "text": "modify signature of lemmas about `mergeSort`.", "pull request": "5378"}
{"Version": "v4.13.0", "section": "Library", "text": "avoid importing `List.Basic` without `List.Impl`.", "pull request": "5245"}
{"Version": "v4.13.0", "section": "Library", "text": "review of List API.", "pull request": "5260"}
{"Version": "v4.13.0", "section": "Library", "text": "review of List API.", "pull request": "5264"}
{"Version": "v4.13.0", "section": "Library", "text": "remove HashMap's duplicated `Pairwise` and `Sublist` from List file.", "pull request": "5269"}
{"Version": "v4.13.0", "section": "Library", "text": "remove `@[simp]` from `List.head_mem` and similar.", "pull request": "5271"}
{"Version": "v4.13.0", "section": "Library", "text": "lemmas about `List.attach`.", "pull request": "5273"}
{"Version": "v4.13.0", "section": "Library", "text": "reverse direction of `List.tail_map`.", "pull request": "5275"}
{"Version": "v4.13.0", "section": "Library", "text": "more `List.attach` lemmas.", "pull request": "5277"}
{"Version": "v4.13.0", "section": "Library", "text": "`List.count` lemmas.", "pull request": "5285"}
{"Version": "v4.13.0", "section": "Library", "text": "use boolean predicates in `List.filter`.", "pull request": "5287"}
{"Version": "v4.13.0", "section": "Library", "text": "`List.mem_ite_nil_left` and analogues.", "pull request": "5289"}
{"Version": "v4.13.0", "section": "Library", "text": "cleanup of `List.findIdx` / `List.take` lemmas.", "pull request": "5293"}
{"Version": "v4.13.0", "section": "Library", "text": "switch primes on `List.getElem_take` lemmas.", "pull request": "5294"}
{"Version": "v4.13.0", "section": "Library", "text": "more `List.findIdx` theorems.", "pull request": "5300"}
{"Version": "v4.13.0", "section": "Library", "text": "fix `List.all/any` lemmas.", "pull request": "5310"}
{"Version": "v4.13.0", "section": "Library", "text": "fix `List.countP` lemmas.", "pull request": "5311"}
{"Version": "v4.13.0", "section": "Library", "text": "`List.tail` lemma.", "pull request": "5316"}
{"Version": "v4.13.0", "section": "Library", "text": "fix implicitness of `List.getElem_mem`.", "pull request": "5331"}
{"Version": "v4.13.0", "section": "Library", "text": "`List.replicate` lemmas.", "pull request": "5350"}
{"Version": "v4.13.0", "section": "Library", "text": "`List.attachWith` lemmas.", "pull request": "5352"}
{"Version": "v4.13.0", "section": "Library", "text": "`List.head_mem_head?`.", "pull request": "5353"}
{"Version": "v4.13.0", "section": "Library", "text": "lemmas about `List.tail`.", "pull request": "5360"}
{"Version": "v4.13.0", "section": "Library", "text": "review of `List.erase` / `List.find` lemmas.", "pull request": "5391"}
{"Version": "v4.13.0", "section": "Library", "text": "`List.fold` / `attach` lemmas.", "pull request": "5392"}
{"Version": "v4.13.0", "section": "Library", "text": "`List.fold` relators.", "pull request": "5393"}
{"Version": "v4.13.0", "section": "Library", "text": "lemmas about `List.maximum?`.", "pull request": "5394"}
{"Version": "v4.13.0", "section": "Library", "text": "theorems about `List.toArray`.", "pull request": "5403"}
{"Version": "v4.13.0", "section": "Library", "text": "reverse direction of `List.set_map`.", "pull request": "5405"}
{"Version": "v4.13.0", "section": "Library", "text": "add lemmas about `List.IsPrefix` (@Command-Master).", "pull request": "5448"}
{"Version": "v4.13.0", "section": "Library", "text": "adds `List.set_replicate_self` lemma.", "pull request": "5460"}
{"Version": "v4.13.0", "section": "Library", "text": "rename `List.maximum?` to `max?`.", "pull request": "5518"}
{"Version": "v4.13.0", "section": "Library", "text": "upstream `List.fold` lemmas.", "pull request": "5519"}
{"Version": "v4.13.0", "section": "Library", "text": "restore `@[simp]` on `List.getElem_mem` etc.", "pull request": "5520"}
{"Version": "v4.13.0", "section": "Library", "text": "List simp fixes.", "pull request": "5521"}
{"Version": "v4.13.0", "section": "Library", "text": "`List.unattach` and simp lemmas.", "pull request": "5550"}
{"Version": "v4.13.0", "section": "Library", "text": "induction-friendly `List.min?_cons`.", "pull request": "5594"}
{"Version": "v4.13.0", "section": "Library", "text": "cleanup imports of `Array.Lemmas`.", "pull request": "5246"}
{"Version": "v4.13.0", "section": "Library", "text": "split `Init.Data.Array.Lemmas` for better bootstrapping.", "pull request": "5255"}
{"Version": "v4.13.0", "section": "Library", "text": "rename `Array.data` to `Array.toList`.", "pull request": "5288"}
{"Version": "v4.13.0", "section": "Library", "text": "cleanup of `List.getElem_append` variants.", "pull request": "5303"}
{"Version": "v4.13.0", "section": "Library", "text": "`Array.not_mem_empty`.", "pull request": "5304"}
{"Version": "v4.13.0", "section": "Library", "text": "reorganization in Array/Basic.", "pull request": "5400"}
{"Version": "v4.13.0", "section": "Library", "text": "make `Array` functions semireducible or use structural recursion.", "pull request": "5420"}
{"Version": "v4.13.0", "section": "Library", "text": "refactor `DecidableEq (Array α)`.", "pull request": "5422"}
{"Version": "v4.13.0", "section": "Library", "text": "refactor of Array, see commits for details.", "pull request": "5452"}
{"Version": "v4.13.0", "section": "Library", "text": "cleanup of Array docstrings after refactor.", "pull request": "5458"}
{"Version": "v4.13.0", "section": "Library", "text": "restore `@[simp]` on `Array.swapAt!_def`.", "pull request": "5461"}
{"Version": "v4.13.0", "section": "Library", "text": "improve Array GetElem lemmas.", "pull request": "5465"}
{"Version": "v4.13.0", "section": "Library", "text": "`Array.foldX` lemmas.", "pull request": "5466"}
{"Version": "v4.13.0", "section": "Library", "text": "@[simp] lemmas about `List.toArray`.", "pull request": "5472"}
{"Version": "v4.13.0", "section": "Library", "text": "reverse simp direction for `toArray_concat`.", "pull request": "5485"}
{"Version": "v4.13.0", "section": "Library", "text": "`Array.eraseReps`.", "pull request": "5514"}
{"Version": "v4.13.0", "section": "Library", "text": "upstream `Array.qsortOrd`.", "pull request": "5515"}
{"Version": "v4.13.0", "section": "Library", "text": "upstream `Subarray.empty`.", "pull request": "5516"}
{"Version": "v4.13.0", "section": "Library", "text": "fix name of `Array.length_toList`.", "pull request": "5526"}
{"Version": "v4.13.0", "section": "Library", "text": "reduce use of deprecated lemmas in Array.", "pull request": "5527"}
{"Version": "v4.13.0", "section": "Library", "text": "cleanup of Array GetElem lemmas.", "pull request": "5534"}
{"Version": "v4.13.0", "section": "Library", "text": "fix `Array.modify` lemmas.", "pull request": "5536"}
{"Version": "v4.13.0", "section": "Library", "text": "upstream `Array.flatten` lemmas.", "pull request": "5551"}
{"Version": "v4.13.0", "section": "Library", "text": "switch obvious cases of array indexing to rely on existing hypothesis (@TomasPuverle).", "pull request": "5552"}
{"Version": "v4.13.0", "section": "Library", "text": "add missing simp to `Array.size_feraseIdx`.", "pull request": "5577"}
{"Version": "v4.13.0", "section": "Library", "text": "`Array/Option.unattach`.", "pull request": "5586"}
{"Version": "v4.13.0", "section": "Library", "text": "remove @[simp] from `Option.pmap/pbind`, add new simp lemmas.", "pull request": "5272"}
{"Version": "v4.13.0", "section": "Library", "text": "restore Option simp confluence.", "pull request": "5307"}
{"Version": "v4.13.0", "section": "Library", "text": "remove @[simp] from `Option.bind_map`.", "pull request": "5354"}
{"Version": "v4.13.0", "section": "Library", "text": "`Option.attach`.", "pull request": "5532"}
{"Version": "v4.13.0", "section": "Library", "text": "fix explicitness of `Option.mem_toList`.", "pull request": "5539"}
{"Version": "v4.13.0", "section": "Library", "text": "add @[simp] to `Nat.add_eq_zero_iff`.", "pull request": "5241"}
{"Version": "v4.13.0", "section": "Library", "text": "Nat bitwise lemmas.", "pull request": "5261"}
{"Version": "v4.13.0", "section": "Library", "text": "`Nat.testBit_add_one` is no longer a global simp lemma.", "pull request": "5262"}
{"Version": "v4.13.0", "section": "Library", "text": "protect some Nat bitwise theorems.", "pull request": "5267"}
{"Version": "v4.13.0", "section": "Library", "text": "rename Nat bitwise lemmas.", "pull request": "5305"}
{"Version": "v4.13.0", "section": "Library", "text": "add `Nat.self_sub_mod` lemma.", "pull request": "5306"}
{"Version": "v4.13.0", "section": "Library", "text": "restore @[simp] to `Nat.lt_off_iff` from upstream.", "pull request": "5503"}
{"Version": "v4.13.0", "section": "Library", "text": "rename `Int.div/mod` to `Int.tdiv/tmod`.", "pull request": "5301"}
{"Version": "v4.13.0", "section": "Library", "text": "add `ediv_nonneg_of_nonpos_of_nonpos` to `DivModLemmas` (@sakehl).", "pull request": "5320"}
{"Version": "v4.13.0", "section": "Library", "text": "missing lemma about `Fin.ofNat'`.", "pull request": "5250"}
{"Version": "v4.13.0", "section": "Library", "text": "`Fin.ofNat'` uses `NeZero`.", "pull request": "5356"}
{"Version": "v4.13.0", "section": "Library", "text": "remove some @[simp] from Fin lemmas.", "pull request": "5379"}
{"Version": "v4.13.0", "section": "Library", "text": "missing Fin @[simp] lemmas.", "pull request": "5380"}
{"Version": "v4.13.0", "section": "Library", "text": "adds DHashMap/HashMap/HashSet `(getKey? / getKey / getKey! / getKeyD).`", "pull request": "5244"}
{"Version": "v4.13.0", "section": "Library", "text": "remove last uses of `Lean.HashSet/HashMap` in library code.", "pull request": "5362"}
{"Version": "v4.13.0", "section": "Library", "text": "`HashSet.ofArray`.", "pull request": "5369"}
{"Version": "v4.13.0", "section": "Library", "text": "`HashSet.partition`.", "pull request": "5370"}
{"Version": "v4.13.0", "section": "Library", "text": "`Singleton` / `Insert` / `Union` instances for `HashMap` and `HashSet`.", "pull request": "5581"}
{"Version": "v4.13.0", "section": "Library", "text": "`HashSet.all`/`any`.", "pull request": "5582"}
{"Version": "v4.13.0", "section": "Library", "text": "`Insert` / `Singleton` / `Union` for `HashMap` / `Set.Raw`.", "pull request": "5590"}
{"Version": "v4.13.0", "section": "Library", "text": "`HashSet.Raw.all`/`any`.", "pull request": "5591"}
{"Version": "v4.13.0", "section": "Library", "text": "upstream some monad lemmas.", "pull request": "5463"}
{"Version": "v4.13.0", "section": "Library", "text": "adjust simp attributes on monad lemmas.", "pull request": "5464"}
{"Version": "v4.13.0", "section": "Library", "text": "more monadic simp lemmas.", "pull request": "5522"}
{"Version": "v4.13.0", "section": "Library", "text": "remove redundant simp annotations.", "pull request": "5251"}
{"Version": "v4.13.0", "section": "Library", "text": "remove Int simp lemmas that cannot fire.", "pull request": "5253"}
{"Version": "v4.13.0", "section": "Library", "text": "some variables on both sides of an iff should be implicit.", "pull request": "5254"}
{"Version": "v4.13.0", "section": "Library", "text": "cleaning up redundant simp lemmas.", "pull request": "5381"}
{"Version": "v4.13.0", "section": "Compiler, runtime, and FFI", "text": "fixes a typo in the C `run_new_frontend` signature.", "pull request": "4685"}
{"Version": "v4.13.0", "section": "Compiler, runtime, and FFI", "text": "IR checker suggests using `noncomputable` for missing definitions.", "pull request": "4729"}
{"Version": "v4.13.0", "section": "Compiler, runtime, and FFI", "text": "adds a shared library for Lake.", "pull request": "5143"}
{"Version": "v4.13.0", "section": "Compiler, runtime, and FFI", "text": "removes (syntactically) duplicate imports (@euprunin).", "pull request": "5437"}
{"Version": "v4.13.0", "section": "Compiler, runtime, and FFI", "text": "updates `src/lake/lakefile.toml` to the adjusted Lake build process.", "pull request": "5462"}
{"Version": "v4.13.0", "section": "Compiler, runtime, and FFI", "text": "removes new shared libs before build to better support Windows.", "pull request": "5541"}
{"Version": "v4.13.0", "section": "Compiler, runtime, and FFI", "text": "make `lean.h` compile with MSVC (@kant2002).", "pull request": "5558"}
{"Version": "v4.13.0", "section": "Compiler, runtime, and FFI", "text": "removes non-conforming size-0 arrays (@eric-wieser).", "pull request": "5564"}
{"Version": "v4.13.0", "section": "Lake", "text": "Reservoir build cache: Lake attempts to fetch a pre-built copy of packages in leanprover or leanprover-community. `--no-cache` or env var can disable. Breaking: a package's extraDep no longer transitively builds dependencies’ extraDep facets.", "pull request": "5486"}
{"Version": "v4.13.0", "section": "Lake", "text": "Reservoir build cache: Lake attempts to fetch a pre-built copy of packages in leanprover or leanprover-community. `--no-cache` or env var can disable. Breaking: a package's extraDep no longer transitively builds dependencies’ extraDep facets.", "pull request": "5572"}
{"Version": "v4.13.0", "section": "Lake", "text": "Reservoir build cache: Lake attempts to fetch a pre-built copy of packages in leanprover or leanprover-community. `--no-cache` or env var can disable. Breaking: a package's extraDep no longer transitively builds dependencies’ extraDep facets.", "pull request": "5583"}
{"Version": "v4.13.0", "section": "Lake", "text": "Reservoir build cache: Lake attempts to fetch a pre-built copy of packages in leanprover or leanprover-community. `--no-cache` or env var can disable. Breaking: a package's extraDep no longer transitively builds dependencies’ extraDep facets.", "pull request": "5600"}
{"Version": "v4.13.0", "section": "Lake", "text": "Reservoir build cache: Lake attempts to fetch a pre-built copy of packages in leanprover or leanprover-community. `--no-cache` or env var can disable. Breaking: a package's extraDep no longer transitively builds dependencies’ extraDep facets.", "pull request": "5641"}
{"Version": "v4.13.0", "section": "Lake", "text": "Reservoir build cache: Lake attempts to fetch a pre-built copy of packages in leanprover or leanprover-community. `--no-cache` or env var can disable. Breaking: a package's extraDep no longer transitively builds dependencies’ extraDep facets.", "pull request": "5642"}
{"Version": "v4.13.0", "section": "Lake", "text": "`lake new` and `lake init` now produce TOML configurations by default.", "pull request": "5504"}
{"Version": "v4.13.0", "section": "Lake", "text": "fixes a serious issue where Lake would delete path dependencies when cleaning up a dependency with an incorrect name.", "pull request": "5878"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "`@[builtin_doc]` attribute (@digama0).", "pull request": "3918"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "explains borrow syntax (@eric-wieser).", "pull request": "4305"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "adds documentation for `groupBy.loop` (@vihdzp).", "pull request": "5349"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "fixes typo in `BitVec.mul` docstring (@llllvvuu).", "pull request": "5473"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "fixes typos in `Lean.MetavarContext` docstrings.", "pull request": "5476"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "removes mention of `Lean.withSeconds` (@alexkeizer).", "pull request": "5481"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "updates docs/tests for `toUIntX` functions (@TomasPuverle).", "pull request": "5497"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "mentions that `inferType` does not ensure type correctness.", "pull request": "5087"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "spelling fixes across doc-strings (@euprunin).", "pull request": "5425"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "spelling fixes across doc-strings (@euprunin).", "pull request": "5426"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "spelling fixes across doc-strings (@euprunin).", "pull request": "5427"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "spelling fixes across doc-strings (@euprunin).", "pull request": "5430"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "spelling fixes across doc-strings (@euprunin).", "pull request": "5431"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "spelling fixes across doc-strings (@euprunin).", "pull request": "5434"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "spelling fixes across doc-strings (@euprunin).", "pull request": "5435"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "spelling fixes across doc-strings (@euprunin).", "pull request": "5436"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "spelling fixes across doc-strings (@euprunin).", "pull request": "5438"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "spelling fixes across doc-strings (@euprunin).", "pull request": "5439"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "spelling fixes across doc-strings (@euprunin).", "pull request": "5440"}
{"Version": "v4.13.0", "section": "Documentation fixes", "text": "spelling fixes across doc-strings (@euprunin).", "pull request": "5599"}
{"Version": "v4.13.0", "section": "Changes to CI", "text": "allows addition of `release-ci` label via comment (@thorimur).", "pull request": "5343"}
{"Version": "v4.13.0", "section": "Changes to CI", "text": "sets check level correctly during workflow (@thorimur).", "pull request": "5344"}
{"Version": "v4.13.0", "section": "Changes to CI", "text": "Mathlib's `lean-pr-testing-NNNN` branches use Batteries' `lean-pr-testing-NNNN` branches.", "pull request": "5444"}
{"Version": "v4.13.0", "section": "Changes to CI", "text": "commit `lake-manifest.json` when updating `lean-pr-testing` branches.", "pull request": "5489"}
{"Version": "v4.13.0", "section": "Changes to CI", "text": "use separate secrets for commenting and branching in `pr-release.yml`.", "pull request": "5490"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "introduces the `bv_decide` tactic for goals involving `BitVec` and `Bool`. It reduces the goal to a SAT instance for an external solver, uses an LRAT proof, and the Lean compiler is part of the TCB. CaDiCaL solver is bundled. Includes counterexample functionality and examples in `tests/lean/run/bv_*`.", "pull request": "5013"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "introduces the `bv_decide` tactic for goals involving `BitVec` and `Bool`. It reduces the goal to a SAT instance for an external solver, uses an LRAT proof, and the Lean compiler is part of the TCB. CaDiCaL solver is bundled. Includes counterexample functionality and examples in `tests/lean/run/bv_*`.", "pull request": "5074"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "introduces the `bv_decide` tactic for goals involving `BitVec` and `Bool`. It reduces the goal to a SAT instance for an external solver, uses an LRAT proof, and the Lean compiler is part of the TCB. CaDiCaL solver is bundled. Includes counterexample functionality and examples in `tests/lean/run/bv_*`.", "pull request": "5100"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "introduces the `bv_decide` tactic for goals involving `BitVec` and `Bool`. It reduces the goal to a SAT instance for an external solver, uses an LRAT proof, and the Lean compiler is part of the TCB. CaDiCaL solver is bundled. Includes counterexample functionality and examples in `tests/lean/run/bv_*`.", "pull request": "5113"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "introduces the `bv_decide` tactic for goals involving `BitVec` and `Bool`. It reduces the goal to a SAT instance for an external solver, uses an LRAT proof, and the Lean compiler is part of the TCB. CaDiCaL solver is bundled. Includes counterexample functionality and examples in `tests/lean/run/bv_*`.", "pull request": "5137"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "introduces the `bv_decide` tactic for goals involving `BitVec` and `Bool`. It reduces the goal to a SAT instance for an external solver, uses an LRAT proof, and the Lean compiler is part of the TCB. CaDiCaL solver is bundled. Includes counterexample functionality and examples in `tests/lean/run/bv_*`.", "pull request": "5203"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "introduces the `bv_decide` tactic for goals involving `BitVec` and `Bool`. It reduces the goal to a SAT instance for an external solver, uses an LRAT proof, and the Lean compiler is part of the TCB. CaDiCaL solver is bundled. Includes counterexample functionality and examples in `tests/lean/run/bv_*`.", "pull request": "5212"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "introduces the `bv_decide` tactic for goals involving `BitVec` and `Bool`. It reduces the goal to a SAT instance for an external solver, uses an LRAT proof, and the Lean compiler is part of the TCB. CaDiCaL solver is bundled. Includes counterexample functionality and examples in `tests/lean/run/bv_*`.", "pull request": "5220"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a panic in the `reducePow` simproc for `simp`.", "pull request": "4988"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "exposes the `index` option to the `dsimp` tactic, which was introduced to `simp` in #4202.", "pull request": "5071"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a panic at `Fin.isValue` simproc in `simp`.", "pull request": "5159"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "renames `simpCtorEq` simproc to `reduceCtorEq` and makes it optional (see breaking changes).", "pull request": "5167"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "renames `simpCtorEq` simproc to `reduceCtorEq` and makes it optional (see breaking changes).", "pull request": "5175"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "ensures `reduceCtorEq` is enabled in the `norm_cast` tactic.", "pull request": "5187"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "modifies the simp debug trace messages to use \"dpre\" and \"dpost\" instead of \"pre\" and \"post\" in definitional rewrite mode. #5054 explains the `reduce` steps in `trace.Debug.Meta.Tactic.simp` messages.", "pull request": "5073"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "reduces default maximum iteration depth of `ext` from 1000000 to 100.", "pull request": "4996"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a bug in `induction` where `let` bindings in minor premises weren't counted correctly.", "pull request": "5117"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a panic in `omega` tactic.", "pull request": "5157"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "improves `arg n` in `conv` to handle subsingleton instance arguments.", "pull request": "5149"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "upstreams the `#time` command.", "pull request": "5044"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "makes `#check` and `#reduce` typecheck the elaborated terms.", "pull request": "5079"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "fixes regression in incrementality where we wouldn't interrupt elaboration of previous doc versions.", "pull request": "4974"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a performance regression in incremental mode.", "pull request": "5004"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "disables incremental body elaboration in presence of `where` clauses in declarations.", "pull request": "5001"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "enables infotrees on the command line for ilean generation.", "pull request": "5018"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "improves performance of info trees in incremental elaboration.", "pull request": "5040"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "improves performance of info trees in incremental elaboration.", "pull request": "5056"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "disables incrementality in the `case .. | ..` tactic.", "pull request": "5090"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "fixes an issue where changing whitespace after the module header could break subsequent commands. Overlaps with #5312.", "pull request": "5312"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "adds `clean_wf` tactic in `decreasing_by` to clean up tactic state. Disabled by `set_option debug.rawDecreasingByGoal false`.", "pull request": "5016"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "adds `clean_wf` tactic in `decreasing_by` to clean up tactic state. Disabled by `set_option debug.rawDecreasingByGoal false`.", "pull request": "5066"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "unifies equational theorems between structural and well-founded recursion. See also #5055 for details.", "pull request": "5055"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "allows mutually recursive functions to use different parameter names in the fixed parameter prefix.", "pull request": "5041"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "adds fine-grained equational lemmas for non-recursive functions. See breaking changes (#4154).", "pull request": "4154"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "adds fine-grained equational lemmas for non-recursive functions. See breaking changes (#4154).", "pull request": "5109"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "unifies equation lemmas for recursive and non-recursive definitions. `backward.eqns.deepRecursiveSplit = false` reverts old behavior. See breaking changes (#5129).", "pull request": "5129"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "unifies equation lemmas for recursive and non-recursive definitions. `backward.eqns.deepRecursiveSplit = false` reverts old behavior. See breaking changes (#5129).", "pull request": "5207"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "adds `f.eq_unfold` lemmas. Lean now produces four rewrite rules: eq_1, eq_2, eq_def, eq_unfold for each function, eq_unfold is especially good for rewriting under binders.", "pull request": "5141"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "fixes bugs in recursion over predicates (#5136).", "pull request": "5136"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "documents that `include` applies only to theorems currently.", "pull request": "5206"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a bug where autoparam errors were associated to the wrong source position.", "pull request": "4926"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "fixes cdot anonymous function expansions so `(· + ·)` becomes `fun x1 x2 => x1 + x2` and not ambiguous notation.", "pull request": "4833"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "improves the tactic that proves array indexing in bounds (#5037).", "pull request": "5037"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a loop in the array indexing tactic when mvars are present.", "pull request": "5119"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "makes the structure type clickable in \"not a field of structure\" errors for instance notation.", "pull request": "5072"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a bug where mutual `inductive` could create terms the kernel rejects.", "pull request": "4717"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a bug where `variable` could fail mixing binder updates and declarations.", "pull request": "5142"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "changes `syntheticHole` parser so hovering over `?_` yields docstring for synthetic holes.", "pull request": "5118"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "uses emoji variant selectors for ✅, ❌, 💥 in messages, improving font selection.", "pull request": "5173"}
{"Version": "v4.12.0", "section": "Language features, tactics, and metaprograms", "text": "fixes a bug in `rename_i` where it could rename implementation detail hypotheses.", "pull request": "5183"}
{"Version": "v4.12.0", "section": "Language server, widgets, and IDE extensions", "text": "resolves two LS bugs, especially on Windows: editing header might fail to restart file worker, or server might not start at all on slow Windows. Also fixes missed messages if a file worker restarts (#4821).", "pull request": "4821"}
{"Version": "v4.12.0", "section": "Language server, widgets, and IDE extensions", "text": "updates the user widget manual.", "pull request": "5006"}
{"Version": "v4.12.0", "section": "Language server, widgets, and IDE extensions", "text": "updates the quickstart guide with new Lean 4 extension display name.", "pull request": "5193"}
{"Version": "v4.12.0", "section": "Language server, widgets, and IDE extensions", "text": "fixes bug where \"import out of date\" messages would accumulate over time.", "pull request": "5185"}
{"Version": "v4.12.0", "section": "Language server, widgets, and IDE extensions", "text": "improves ilean loading performance by ~2x (#4900). Optimizes JSON parsing. See PR for details.", "pull request": "4900"}
{"Version": "v4.12.0", "section": "Language server, widgets, and IDE extensions", "text": "localizes an instance in `Lsp.Diagnostics` to fix issues (#5031).", "pull request": "5031"}
{"Version": "v4.12.0", "section": "Pretty printing", "text": "introduces `@[app_delab]` macro for constant-specific delaborators. Syntax `@[app_delab ident]` expands to `@[delab app.name]`.", "pull request": "4976"}
{"Version": "v4.12.0", "section": "Pretty printing", "text": "fixes a bug in the pretty printer for structure projections, which can appear in type mismatch errors. Improves hover in `#print` for structures.", "pull request": "4982"}
{"Version": "v4.12.0", "section": "Pretty printing", "text": "adds `pp.exprSizes` debug option. When true, printed expressions get `[size a/b/c]` prefix showing sizes with/without sharing.", "pull request": "5218"}
{"Version": "v4.12.0", "section": "Pretty printing", "text": "adds `pp.exprSizes` debug option. When true, printed expressions get `[size a/b/c]` prefix showing sizes with/without sharing.", "pull request": "5239"}
{"Version": "v4.12.0", "section": "Library", "text": "swaps the parameters to `Membership.mem`, so the set-like `CoeSort` refers to `fun x => mem s x`. See breaking changes (#5020).", "pull request": "5020"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `@[ext]` attribute to `Array.ext` and deprecates `Array.get_modify` (#4957).", "pull request": "4970"}
{"Version": "v4.12.0", "section": "Library", "text": "deprecates `Array.get_modify` (#4970).", "pull request": "4957"}
{"Version": "v4.12.0", "section": "Library", "text": "upstreams `List.findIdx` lemmas.", "pull request": "4995"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.Sublist` lemmas, some upstreamed. Also fixes implicitness in `refl/rfl` lemma binders. (#5029, #5048, #5132, #5077).", "pull request": "5029"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.Sublist` lemmas, some upstreamed. Also fixes implicitness in `refl/rfl` lemma binders. (#5029, #5048, #5132, #5077).", "pull request": "5048"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.Sublist` lemmas, some upstreamed. Also fixes implicitness in `refl/rfl` lemma binders. (#5029, #5048, #5132, #5077).", "pull request": "5132"}
{"Version": "v4.12.0", "section": "Library", "text": "fixes implicitness in `List.Sublist` lemma binders (#5077).", "pull request": "5077"}
{"Version": "v4.12.0", "section": "Library", "text": "upstreams `List.Pairwise` lemmas.", "pull request": "5047"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.find?/findSome?/findIdx?` theorems (#5053, #5124, #5161).", "pull request": "5053"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.find?/findSome?/findIdx?` theorems (#5053, #5124, #5161).", "pull request": "5124"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.find?/findSome?/findIdx?` theorems (#5053, #5124, #5161).", "pull request": "5161"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.foldlRecOn` and `List.foldrRecOn` to prove theorems about `foldl`/`foldr` (#5039).", "pull request": "5039"}
{"Version": "v4.12.0", "section": "Library", "text": "upstreams `List.Perm` (#5069).", "pull request": "5069"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.mergeSort` with fast `@[csimp]` implementation (#5092, #5107).", "pull request": "5092"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.mergeSort` with fast `@[csimp]` implementation (#5092, #5107).", "pull request": "5107"}
{"Version": "v4.12.0", "section": "Library", "text": "makes the simp lemmas for `List.subset` more aggressive (#5103).", "pull request": "5103"}
{"Version": "v4.12.0", "section": "Library", "text": "changes the statement of `List.getLast?_cons` (#5106).", "pull request": "5106"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.range` and `List.iota` lemmas (#5123, #5158).", "pull request": "5123"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.range` and `List.iota` lemmas (#5123, #5158).", "pull request": "5158"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.join` lemmas (#5130).", "pull request": "5130"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.append` lemmas (#5131).", "pull request": "5131"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.erase(|P|Idx)` lemmas (#5152).", "pull request": "5152"}
{"Version": "v4.12.0", "section": "Library", "text": "misc lemma updates for `List` (#5127).", "pull request": "5127"}
{"Version": "v4.12.0", "section": "Library", "text": "lemmas about `List.attach` / `List.pmap` (#5153, #5160).", "pull request": "5153"}
{"Version": "v4.12.0", "section": "Library", "text": "lemmas about `List.attach` / `List.pmap` (#5153, #5160).", "pull request": "5160"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.find?` and `List.range'/range/iota` lemmas (#5164, #5177, #5215).", "pull request": "5164"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.find?` and `List.range'/range/iota` lemmas (#5164, #5177, #5215).", "pull request": "5177"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.find?` and `List.range'/range/iota` lemmas (#5164, #5177, #5215).", "pull request": "5215"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `List.Pairwise_erase` etc. (#5196).", "pull request": "5196"}
{"Version": "v4.12.0", "section": "Library", "text": "improves confluence of `List` simp lemmas (#5151, #5163, #5105, #5102).", "pull request": "5151"}
{"Version": "v4.12.0", "section": "Library", "text": "improves confluence of `List` simp lemmas (#5151, #5163, #5105, #5102).", "pull request": "5163"}
{"Version": "v4.12.0", "section": "Library", "text": "adjust `List` simp lemmas (#5105, #5102).", "pull request": "5105"}
{"Version": "v4.12.0", "section": "Library", "text": "adjust `List` simp lemmas (#5105, #5102).", "pull request": "5102"}
{"Version": "v4.12.0", "section": "Library", "text": "removes `List.getLast_eq_iff_getLast_eq_some` as a simp lemma (#5178).", "pull request": "5178"}
{"Version": "v4.12.0", "section": "Library", "text": "reverses meaning of `List.getElem_drop` / `List.getElem_drop'` (#5210).", "pull request": "5210"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `Nat.add_left_eq_self` and similar (#5104).", "pull request": "5104"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `Nat.and_xor_distrib_(left|right)` (#5146).", "pull request": "5146"}
{"Version": "v4.12.0", "section": "Library", "text": "improves confluence of `Nat` and `Int` simp lemmas (#5148, #5190).", "pull request": "5148"}
{"Version": "v4.12.0", "section": "Library", "text": "improves confluence of `Nat` and `Int` simp lemmas (#5148, #5190).", "pull request": "5190"}
{"Version": "v4.12.0", "section": "Library", "text": "adjusts `Int` simp lemmas (#5165).", "pull request": "5165"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `Int` lemmas about `neg` with `emod`/`mod` (#5166).", "pull request": "5166"}
{"Version": "v4.12.0", "section": "Library", "text": "reverses direction of `Int.toNat_sub` simp lemma (#5208).", "pull request": "5208"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `Nat.bitwise` lemmas (#5209).", "pull request": "5209"}
{"Version": "v4.12.0", "section": "Library", "text": "corrects docstrings for integer division and modulus (#5230).", "pull request": "5230"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `Option` lemmas (#5128, #5154).", "pull request": "5128"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `Option` lemmas (#5128, #5154).", "pull request": "5154"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `sshiftRight` bitblasting to `BitVec` (#4889).", "pull request": "4889"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `Std.Associative` and `Std.Commutative` for `BitVec.[and|or|xor]` (#4981).", "pull request": "4981"}
{"Version": "v4.12.0", "section": "Library", "text": "enables `missingDocs` error for `BitVec` modules (#4913).", "pull request": "4913"}
{"Version": "v4.12.0", "section": "Library", "text": "makes parameter names more consistent in `BitVec` (#4930).", "pull request": "4930"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `BitVec.intMin`, introduces `boolToPropSimps` set for boolean→propositional (#5098).", "pull request": "5098"}
{"Version": "v4.12.0", "section": "Library", "text": "renames `BitVec.getLsb` etc. to `BitVec.getLsbD`, aligning with `List`/`Array` naming (#5200, #5217).", "pull request": "5200"}
{"Version": "v4.12.0", "section": "Library", "text": "renames `BitVec.getLsb` etc. to `BitVec.getLsbD`, aligning with `List`/`Array` naming (#5200, #5217).", "pull request": "5217"}
{"Version": "v4.12.0", "section": "Library", "text": "various BitVec theorems (#4977, #4951, #4667, #5007, #4997, #5083, #5081, #4392).", "pull request": "4977"}
{"Version": "v4.12.0", "section": "Library", "text": "various BitVec theorems (#4977, #4951, #4667, #5007, #4997, #5083, #5081, #4392).", "pull request": "4951"}
{"Version": "v4.12.0", "section": "Library", "text": "various BitVec theorems (#4977, #4951, #4667, #5007, #4997, #5083, #5081, #4392).", "pull request": "4667"}
{"Version": "v4.12.0", "section": "Library", "text": "various BitVec theorems (#4977, #4951, #4667, #5007, #4997, #5083, #5081, #4392).", "pull request": "5007"}
{"Version": "v4.12.0", "section": "Library", "text": "various BitVec theorems (#4977, #4951, #4667, #5007, #4997, #5083, #5081, #4392).", "pull request": "4997"}
{"Version": "v4.12.0", "section": "Library", "text": "various BitVec theorems (#4977, #4951, #4667, #5007, #4997, #5083, #5081, #4392).", "pull request": "5083"}
{"Version": "v4.12.0", "section": "Library", "text": "various BitVec theorems (#4977, #4951, #4667, #5007, #4997, #5083, #5081, #4392).", "pull request": "5081"}
{"Version": "v4.12.0", "section": "Library", "text": "various BitVec theorems (#4977, #4951, #4667, #5007, #4997, #5083, #5081, #4392).", "pull request": "4392"}
{"Version": "v4.12.0", "section": "Library", "text": "fixes naming convention for `UInt` lemmas (#4514).", "pull request": "4514"}
{"Version": "v4.12.0", "section": "Library", "text": "deprecates variants of hash map query methods, switching `Lean.HashMap`→`Std.HashMap` (#4943).", "pull request": "4943"}
{"Version": "v4.12.0", "section": "Library", "text": "switches library/Lean to `Std.HashMap`/`Std.HashSet` (#4917).", "pull request": "4917"}
{"Version": "v4.12.0", "section": "Library", "text": "deprecates `Lean.HashMap` and `Lean.HashSet` (#4954).", "pull request": "4954"}
{"Version": "v4.12.0", "section": "Library", "text": "cleans up lemma parameters in HashMap/HashSet (#5023).", "pull request": "5023"}
{"Version": "v4.12.0", "section": "Library", "text": "adds definitions of SAT/CNF in `Std.Sat` for `bv_decide` (#4933).", "pull request": "4933"}
{"Version": "v4.12.0", "section": "Library", "text": "defines \"and-inverter graphs\" (AIGs) for `Std.Sat` (#4953).", "pull request": "4953"}
{"Version": "v4.12.0", "section": "Library", "text": "generalizes `Parsec` for iterable data, moves from `Lean.Data.Parsec` to `Std.Internal.Parsec`. Breaking changes (#4774).", "pull request": "4774"}
{"Version": "v4.12.0", "section": "Library", "text": "moves `Lean.Data.Parsec` to `Std.Internal.Parsec` for bootstrapping (#5115).", "pull request": "5115"}
{"Version": "v4.12.0", "section": "Library", "text": "upstreams `Thunk.ext` (#4969).", "pull request": "4969"}
{"Version": "v4.12.0", "section": "Library", "text": "`IO.FS.lines` now handles `\\r\\n` on all OSes (#4973).", "pull request": "4973"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `createTempFile`/`withTempFile` for secure temporary files (#5125).", "pull request": "5125"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `Array`, `Bool`, and `Prod` utilities from LeanSAT (#4945).", "pull request": "4945"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `Relation.TransGen.trans` (#4960).", "pull request": "4960"}
{"Version": "v4.12.0", "section": "Library", "text": "states `WellFoundedRelation Nat` using `<` not `Nat.lt` (#5012).", "pull request": "5012"}
{"Version": "v4.12.0", "section": "Library", "text": "uses `≠` in `Fin.ne_of_val_ne` (#5011).", "pull request": "5011"}
{"Version": "v4.12.0", "section": "Library", "text": "upstreams `Fin.le_antisymm` (#5197).", "pull request": "5197"}
{"Version": "v4.12.0", "section": "Library", "text": "reduces usage of `refine'` (#5042).", "pull request": "5042"}
{"Version": "v4.12.0", "section": "Library", "text": "adds about `if-then-else` and `Option` (#5101).", "pull request": "5101"}
{"Version": "v4.12.0", "section": "Library", "text": "adds basic instances for `ULift` and `PLift` (#5112).", "pull request": "5112"}
{"Version": "v4.12.0", "section": "Library", "text": "fixes from running the simpNF linter over Lean (#5133, #5168).", "pull request": "5133"}
{"Version": "v4.12.0", "section": "Library", "text": "fixes from running the simpNF linter over Lean (#5133, #5168).", "pull request": "5168"}
{"Version": "v4.12.0", "section": "Library", "text": "removes a bad simp lemma in `omega` (#5156).", "pull request": "5156"}
{"Version": "v4.12.0", "section": "Library", "text": "improves confluence of `Bool` simp lemmas (#5155).", "pull request": "5155"}
{"Version": "v4.12.0", "section": "Library", "text": "improves confluence of `Function.comp` simp lemmas (#5162).", "pull request": "5162"}
{"Version": "v4.12.0", "section": "Library", "text": "improves confluence of `if-then-else` simp lemmas (#5191).", "pull request": "5191"}
{"Version": "v4.12.0", "section": "Library", "text": "adds `@[elab_as_elim]` to `Quot.rec`, `Nat.strongInductionOn`, etc. Renames `Nat.strongInductionOn`→`Nat.strongRecOn` (#5147, deprecated in #5179).", "pull request": "5147"}
{"Version": "v4.12.0", "section": "Library", "text": "renames `Nat.strongInductionOn`→`Nat.strongRecOn` (deprecated in #5179).", "pull request": "5179"}
{"Version": "v4.12.0", "section": "Library", "text": "disables some simp lemmas with bad discrimination tree keys (#5180).", "pull request": "5180"}
{"Version": "v4.12.0", "section": "Library", "text": "cleans up leaked internal simp lemmas (#5189).", "pull request": "5189"}
{"Version": "v4.12.0", "section": "Library", "text": "cleans up `allowUnsafeReducibility` (#5198).", "pull request": "5198"}
{"Version": "v4.12.0", "section": "Library", "text": "removes unused lemmas from some `simp` tactics (#5229).", "pull request": "5229"}
{"Version": "v4.12.0", "section": "Library", "text": "removes >6 month old deprecations (#5199).", "pull request": "5199"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "rewrote some core algorithms in C++ for performance. `instantiateLevelMVars`, `instantiateExprMVars` are ~30% faster. (#4910, #4912, #4915, #4922, #4931).", "pull request": "4910"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "rewrote some core algorithms in C++ for performance. `instantiateLevelMVars`, `instantiateExprMVars` are ~30% faster. (#4910, #4912, #4915, #4922, #4931).", "pull request": "4912"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "rewrote some core algorithms in C++ for performance. `instantiateLevelMVars`, `instantiateExprMVars` are ~30% faster. (#4910, #4912, #4915, #4922, #4931).", "pull request": "4915"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "rewrote some core algorithms in C++ for performance. `instantiateLevelMVars`, `instantiateExprMVars` are ~30% faster. (#4910, #4912, #4915, #4922, #4931).", "pull request": "4922"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "rewrote some core algorithms in C++ for performance. `instantiateLevelMVars`, `instantiateExprMVars` are ~30% faster. (#4910, #4912, #4915, #4922, #4931).", "pull request": "4931"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "optimizes kernel's `Expr` equality test (#4934).", "pull request": "4934"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "fixes bug in hashing for the kernel's `Expr` equality test (#4990).", "pull request": "4990"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "skips some `PreDefinition` transformations if not needed (#4935, #4936).", "pull request": "4935"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "skips some `PreDefinition` transformations if not needed (#4935, #4936).", "pull request": "4936"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "adds caching for visited exprs at `CheckAssignmentQuick` in `ExprDefEq` (#5225).", "pull request": "5225"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "maximizes term sharing in `instantiateMVarDeclMVars` (#5226).", "pull request": "5226"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "adds profiling for `instantiateMVars` in `Lean.Elab.MutualDef` (#4923).", "pull request": "4923"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "adds diagnostics for large theorems, configured by `diagnostics.threshold.proofSize` (#4924).", "pull request": "4924"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "improves display of diagnostic results (#4897).", "pull request": "4897"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "cleans up `Expr.betaRev` (#4921).", "pull request": "4921"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "fixes tests so we don't write to stdout from separate threads (#4940).", "pull request": "4940"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "documents that `stderrAsMessages` is now default on the CLI (#4955).", "pull request": "4955"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "updates macOS build docs (#4647).", "pull request": "4647"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "makes direct mvar assignments take precedence over delayed ones in `instantiateMVars` (#4987).", "pull request": "4987"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "adds linter name to errors if a linter crashes (#4967).", "pull request": "4967"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "cleans up command line snapshots logic (#5043).", "pull request": "5043"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "minimizes some imports (#5067).", "pull request": "5067"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "generalizes the monad for `addMatcherInfo` (#5068).", "pull request": "5068"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "adds missing test for #5126 (#f71a1fb).", "pull request": "5126"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "restores a test (#5201).", "pull request": "5201"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "fixes a bug where label attributes did not pass on the attribute kind (#3698).", "pull request": "3698"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "typo fixes (#5080, #5150, #5202).", "pull request": "5080"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "typo fixes (#5080, #5150, #5202).", "pull request": "5150"}
{"Version": "v4.12.0", "section": "Lean internals", "text": "typo fixes (#5080, #5150, #5202).", "pull request": "5202"}
{"Version": "v4.12.0", "section": "Compiler, runtime, and FFI", "text": "moves frontend to new snapshot architecture (#3106). `Frontend.processCommand` and `FrontendM` remain but not used by Lean core.", "pull request": "3106"}
{"Version": "v4.12.0", "section": "Compiler, runtime, and FFI", "text": "adds missing include in runtime for `AUTO_THREAD_FINALIZATION` on Windows (#4919).", "pull request": "4919"}
{"Version": "v4.12.0", "section": "Compiler, runtime, and FFI", "text": "adds more `LEAN_EXPORT`s for Windows (#4941).", "pull request": "4941"}
{"Version": "v4.12.0", "section": "Compiler, runtime, and FFI", "text": "improves formatting of CLI help text (#4911).", "pull request": "4911"}
{"Version": "v4.12.0", "section": "Compiler, runtime, and FFI", "text": "improves file read/write: `readBinFile` uses fewer syscalls, `Handle.getLine` no longer tripped by NUL (#4950).", "pull request": "4950"}
{"Version": "v4.12.0", "section": "Compiler, runtime, and FFI", "text": "handles SIGBUS for stack overflows (#4971).", "pull request": "4971"}
{"Version": "v4.12.0", "section": "Compiler, runtime, and FFI", "text": "avoids overwriting existing signal handlers (#5062), referencing rust-lang/rust#69685.", "pull request": "5062"}
{"Version": "v4.12.0", "section": "Compiler, runtime, and FFI", "text": "improves Windows build by splitting `libleanshared`, removing `LEAN_EXPORT` denylist, adds missing exports (#4860).", "pull request": "4860"}
{"Version": "v4.12.0", "section": "Compiler, runtime, and FFI", "text": "ensures panics go to Lean's stderr, so they're visible in LS and command line (#4952).", "pull request": "4952"}
{"Version": "v4.12.0", "section": "Compiler, runtime, and FFI", "text": "links LibUV (#4963). LibUV is now required for building Lean from source (see breaking changes).", "pull request": "4963"}
{"Version": "v4.12.0", "section": "Lake", "text": "removes dead code (#5030).", "pull request": "5030"}
{"Version": "v4.12.0", "section": "Lake", "text": "adds fields to package config for Reservoir (#4770). See PR for details.", "pull request": "4770"}
{"Version": "v4.12.0", "section": "DevOps/CI", "text": "improves release checklist (#4914, #4937).", "pull request": "4914"}
{"Version": "v4.12.0", "section": "DevOps/CI", "text": "improves release checklist (#4914, #4937).", "pull request": "4937"}
{"Version": "v4.12.0", "section": "DevOps/CI", "text": "ignores stale leanpkg tests (#4925).", "pull request": "4925"}
{"Version": "v4.12.0", "section": "DevOps/CI", "text": "upgrades `actions/cache` in CI (#5003).", "pull request": "5003"}
{"Version": "v4.12.0", "section": "DevOps/CI", "text": "sets `save-always` in cache actions (#5010).", "pull request": "5010"}
{"Version": "v4.12.0", "section": "DevOps/CI", "text": "adds more libuv search patterns for speedcenter (#5008).", "pull request": "5008"}
{"Version": "v4.12.0", "section": "DevOps/CI", "text": "reduces runs for \"fast\" benchmarks from 10 to 3 in speedcenter (#5009).", "pull request": "5009"}
{"Version": "v4.12.0", "section": "DevOps/CI", "text": "adjusts lakefile editing to new `git` syntax in `pr-release` (#5014).", "pull request": "5014"}
{"Version": "v4.12.0", "section": "DevOps/CI", "text": "passes `--retry` to `curl` in `pr-release` (#5025).", "pull request": "5025"}
{"Version": "v4.12.0", "section": "DevOps/CI", "text": "builds MacOS Aarch64 release for PRs by default (#5022).", "pull request": "5022"}
{"Version": "v4.12.0", "section": "DevOps/CI", "text": "adds libuv to the MacOS docs (#5045).", "pull request": "5045"}
{"Version": "v4.12.0", "section": "DevOps/CI", "text": "fixes the install name of `libleanshared_1` on macOS (#5034).", "pull request": "5034"}
{"Version": "v4.12.0", "section": "DevOps/CI", "text": "fixes Windows stage 0 (#5051).", "pull request": "5051"}
{"Version": "v4.12.0", "section": "DevOps/CI", "text": "fixes 32bit stage 0 builds (#5052).", "pull request": "5052"}
{"Version": "v4.12.0", "section": "DevOps/CI", "text": "avoids rebuilding `leanmanifest` in each build (#5057).", "pull request": "5057"}
{"Version": "v4.12.0", "section": "DevOps/CI", "text": "makes `restart-on-label` filter by commit SHA (#5099).", "pull request": "5099"}
{"Version": "v4.12.0", "section": "DevOps/CI", "text": "adds CaDiCaL (#4325).", "pull request": "4325"}
{"Version": "v4.12.0", "section": "Breaking changes", "text": "LibUV is now required to build Lean from source. Devs compiling Lean themselves must install LibUV. (#4963)", "pull request": "4963"}
{"Version": "v4.12.0", "section": "Breaking changes", "text": "Recursive defs with `decreasing_by` that begin with `simp_wf` may break. Remove `simp_wf` or replace with `simp`. (#5016)", "pull request": "5016"}
{"Version": "v4.12.0", "section": "Breaking changes", "text": "Behavior changed for `rw [f]` when `f` is a non-recursive function defined by pattern matching. For example, `rw [Option.map]` now fails. Remedies: split on parameter, use `f.eq_def`, or `set_option backward.eqns.nonrecursive false`. (#4154)", "pull request": "4154"}
{"Version": "v4.12.0", "section": "Breaking changes", "text": "Unified equation lemmas for recursive and non-recursive functions adds more eq lemmas. Might break rewrites if numbering changed. See #5129, #5207. Also can set `backward.eqns.deepRecursiveSplit false`. (#5129)", "pull request": "5129"}
{"Version": "v4.12.0", "section": "Breaking changes", "text": "The `reduceCtorEq` simproc is now optional. Might need `simp only [reduceCtorEq]`. (#5167)", "pull request": "5167"}
{"Version": "v4.12.0", "section": "Breaking changes", "text": "`Nat.strongInductionOn` → `Nat.strongRecOn`, `Nat.caseStrongInductionOn` → `Nat.caseStrongRecOn`. (#5147)", "pull request": "5147"}
{"Version": "v4.12.0", "section": "Breaking changes", "text": "The parameters to `Membership.mem` are swapped, which affects `SetLike` usage. (#5020)", "pull request": "5020"}
{"Version": "v4.12.0", "section": "Breaking changes", "text": "`List.getElem_drop` and `List.getElem_drop'` got reversed. (#5210)", "pull request": "5210"}
{"Version": "v4.12.0", "section": "Breaking changes", "text": "`Parsec` moved from `Lean.Data.Parsec` to `Std.Internal.Parsec`. It's now more general. For strings, use `Parser` in `Std.Internal.Parsec.String`. (#4774)", "pull request": "4774"}
{"Version": "v4.12.0", "section": "Breaking changes", "text": "`Lean.HashMap` and `Lean.HashSet` are deprecated in favor of `Std.HashMap/Std.HashSet`. Query functions are renamed, `map[key]` expects presence. (#4943, #4954)", "pull request": "4943"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "The variable inclusion mechanism has been changed. Like before, when a definition mentions a variable, Lean will add it as an argument of the definition, but now in theorem bodies, variables are not included based on usage in order to ensure that changes to the proof cannot change the statement of the overall theorem. Instead, variables are only available to the proof if they have been mentioned in the theorem header or in an include command or are instance implicit and depend only on such variables. The omit command can be used to omit included variables. See breaking changes below. PR references follow.", "pull request": "4883"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Structural recursion can now be explicitly requested using `termination_by structural x` in analogy to the existing `termination_by x` syntax for well-founded recursion. See PR for details.", "pull request": "4542"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Fixes a bug that could lead to ill-typed terms in structural recursion. See PR for details.", "pull request": "4672"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "The `termination_by?` syntax no longer forces well-founded recursion. When structural recursion is inferred, it prints the result using `termination_by structural` syntax.", "pull request": "N/A"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Mutual structural recursion is now supported, both for mutual recursion over a non-mutual data type, as well as recursion over mutual or nested data types. Nested structural recursion is still not supported. The system also generates functional induction principles (f.induct, f.mutual_induct) for these definitions.", "pull request": "4639"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Unnecessary termination_by clauses now produce warnings, not errors.", "pull request": "4809"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Improves handling of nested structural recursion through non-recursive types in certain cases.", "pull request": "4831"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Improves structural recursion over inductive predicates with reflexive arguments.", "pull request": "4839"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Sets Simp.Config.implicitDefEqProofs to true by default (simp tactic).", "pull request": "4784"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Normalizes the order of constraints in error messages (omega tactic).", "pull request": "4612"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Prevents pushing casts into multiplications unless it produces a non-trivial linear combination (omega tactic).", "pull request": "469l"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Decide tactic now uses at least default transparency when reducing the Decidable instance.", "pull request": "4711"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Adds detailed feedback on decide tactic failure, including blame for non-reducing or classical instances, with hints for solutions.", "pull request": "4674"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Makes @[ext] realize ext_iff theorems from user ext theorems. Also includes more robust local/scoped usage. The ext_iff theorem preserves instance implicit binder types rather than making all binder types implicit.", "pull request": "4762"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Makes 'go to definition' work for @[ext] generated lemmas. Adjusts core library usage of ext_iff generation.", "pull request": "4694"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Makes ext_iff theorem preserve inst implicit binder types rather than making all binder types implicit.", "pull request": "4710"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Introduces a safer #eval that prevents evaluation of terms containing sorry, helping avoid Lean process crashes. A new #eval! command reverts to the previous unsafe behavior.", "pull request": "4810"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Adjusts a test to accommodate the new #eval safety checks.", "pull request": "4829"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Adds #discr_tree_key and #discr_tree_simp_key commands for debugging discrimination tree keys, including simp lemma left-hand side transformations.", "pull request": "4447"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Changes option parsing to allow user-defined options from the command line. Initial options are re-parsed and validated after importing. Also discards 'weak.'-prefixed command line option assignments if the underlying option does not exist.", "pull request": "4741"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Improves the construction of the BEq deriving handler, enabling better code generation.", "pull request": "7253ef"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Improves the construction of the BEq deriving handler, enabling better code generation.", "pull request": "a04f3c"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Makes BEq deriving handler work when there are dependently typed fields.", "pull request": "86af04"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Refactors DecidableEq deriving to use 'termination_by structural'.", "pull request": "4826"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Adds unresolveNameGlobalAvoidingLocals to metaprogramming support.", "pull request": "4593"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Deletes deprecated functions from 2022 in Lean's metaprogramming layer.", "pull request": "4618"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Adds Meta.lambdaBoundedTelescope to metaprogramming support.", "pull request": "4642"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Adds Meta.withErasedFVars for entering a context where certain fvars are removed from the local context.", "pull request": "4731"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Adds assignment validation at closeMainGoal, preventing tactics from bypassing the occurs check via exact, etc.", "pull request": "4777"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Introduces Lean.Meta.PProdN for packing and projecting nested PProds in metaprogramming code.", "pull request": "4807"}
{"Version": "v4.11.0", "section": "Language features, tactics, and metaprograms", "text": "Fixes Syntax.unsetTrailing, enabling 'go to definition' to work on the last module name in an import block.", "pull request": "5170"}
{"Version": "v4.11.0", "section": "Language server, widgets, and IDE extensions", "text": "Responses to info view requests come as soon as the relevant tactic finishes execution.", "pull request": "4727"}
{"Version": "v4.11.0", "section": "Language server, widgets, and IDE extensions", "text": "Whitespace changes do not invalidate imports, so starting to type the first declaration after imports no longer triggers reloading them.", "pull request": "4580"}
{"Version": "v4.11.0", "section": "Language server, widgets, and IDE extensions", "text": "Fixes an issue where hovering over unimported builtin names could cause a panic.", "pull request": "4780"}
{"Version": "v4.11.0", "section": "Pretty printing", "text": "Fixes pp.instantiateMVars setting and changes its default to true.", "pull request": "4558"}
{"Version": "v4.11.0", "section": "Pretty printing", "text": "Ensures syntax nodes always run their formatters, fixing an issue with ppSpace in macros or elab commands not producing a space.", "pull request": "4631"}
{"Version": "v4.11.0", "section": "Pretty printing", "text": "Fixes a bug with overly hoverable signatures in #check caused by pp.tagAppFns being set. Hover is now more precise.", "pull request": "4665"}
{"Version": "v4.11.0", "section": "Pretty printing", "text": "Makes match pretty printer obey pp.explicit, so hovering over a match in Infoview shows the underlying term if explicit is on.", "pull request": "4724"}
{"Version": "v4.11.0", "section": "Pretty printing", "text": "Documents why anonymous constructor notation is not flattened in pretty printing.", "pull request": "4764"}
{"Version": "v4.11.0", "section": "Pretty printing", "text": "Parenthesizer changes so only parentheses are hoverable. The parentheses 'steal' the term info from the enclosed expression.", "pull request": "4786"}
{"Version": "v4.11.0", "section": "Pretty printing", "text": "Allows arbitrarily long sequences of optional arguments to be omitted from the end of applications, rather than just one.", "pull request": "4854"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds bitwise lemmas Nat.and_le_(left|right).", "pull request": "4597"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds simprocs for simplifying bit expressions on Nat.", "pull request": "4874"}
{"Version": "v4.11.0", "section": "Library", "text": "Fixes performance of HPow Int Nat Int synthesis by rewriting as a NatPow Int instance.", "pull request": "4903"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds lemmas for UInt* and Fin, including *.and_toNat support.", "pull request": "4605"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds *.and_toNat for UInt* and Fin, among others.", "pull request": "4629"}
{"Version": "v4.11.0", "section": "Library", "text": "Option: adds get lemmas such as Option.get for more robust rewriting.", "pull request": "4599"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds Option.or, a strict version of Option.orElse in the second argument.", "pull request": "4600"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds getElem_congr for rewriting indices in GetElem operations.", "pull request": "4603"}
{"Version": "v4.11.0", "section": "Library", "text": "Upstreams List.attach, Array.attach, Subset, Sublist, and Pairwise/Nodup from Batteries, plus more. Adjusts List.replicate simps, simprocs, reorg of list getters, simprocs for literal array indexing, etc. Many references below.", "pull request": "4586"}
{"Version": "v4.11.0", "section": "Library", "text": "Upstreams List.Subset and List.Sublist from Batteries, plus more improvements. See also #4697, #4706, #4720, #4836, #4837, #4855, #4856, #4866, #4865 for further expansions of List API from mathlib/batteries synergy.", "pull request": "4697"}
{"Version": "v4.11.0", "section": "Library", "text": "Upstreams List.Pairwise, List.Nodup from Batteries. Adds basic material. Also see #4707 for more Pairwise/Nodup testing, #4790 removing typeclass assumptions on List.Nodup.eraseP, etc.", "pull request": "4706"}
{"Version": "v4.11.0", "section": "Library", "text": "Upstreams more List.erase API. Also see #4835 cleanup, #4843, #4868, #4877 corrections to List.Subset lemmas, #4882 usage in subexpressions, etc.", "pull request": "4720"}
{"Version": "v4.11.0", "section": "Library", "text": "Upstreams List.IsPrefix, List.IsSuffix, List.IsInfix plus Decidable instances (#4836, #4837).", "pull request": "4836"}
{"Version": "v4.11.0", "section": "Library", "text": "Upstreams List.attach, List.findIdx, List.indexOf, List.countP, List.count, List.range' (#4855).", "pull request": "4855"}
{"Version": "v4.11.0", "section": "Library", "text": "Upstreams more List lemmas (#4856).", "pull request": "4856"}
{"Version": "v4.11.0", "section": "Library", "text": "Upstreams List.pairwise_iff_getElem (#4866).", "pull request": "4866"}
{"Version": "v4.11.0", "section": "Library", "text": "Upstreams List.eraseIdx lemmas (#4865).", "pull request": "4865"}
{"Version": "v4.11.0", "section": "Library", "text": "Adjusts List.replicate simp lemmas and simprocs for more consistent rewriting.", "pull request": "4687"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds characterizations of List.Sublist (#4704).", "pull request": "4704"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds simp normal form tests for List.Pairwise and List.Nodup (#4707).", "pull request": "4707"}
{"Version": "v4.11.0", "section": "Library", "text": "Reorganizes lemmas on list getters (#4708, #4815).", "pull request": "4708"}
{"Version": "v4.11.0", "section": "Library", "text": "Reorganizes lemmas on list getters (#4708, #4815).", "pull request": "4815"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds simprocs for literal array accesses like #[1,2,3][2] (#4765).", "pull request": "4765"}
{"Version": "v4.11.0", "section": "Library", "text": "Removes typeclass assumptions for List.Nodup.eraseP (#4790).", "pull request": "4790"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds efficient usize functions for array types (#4801).", "pull request": "4801"}
{"Version": "v4.11.0", "section": "Library", "text": "List.filterMapM now runs left-to-right (#4820). Breaking change in monadic side effects ordering.", "pull request": "4820"}
{"Version": "v4.11.0", "section": "Library", "text": "Fills in and cleans up gaps in List API (#4835).", "pull request": "4835"}
{"Version": "v4.11.0", "section": "Library", "text": "Corrects List.Subset lemmas (#4843, #4868, #4877).", "pull request": "4843"}
{"Version": "v4.11.0", "section": "Library", "text": "Corrects List.Subset lemmas (#4843, #4868, #4877).", "pull request": "4868"}
{"Version": "v4.11.0", "section": "Library", "text": "Corrects List.Subset lemmas (#4843, #4868, #4877).", "pull request": "4877"}
{"Version": "v4.11.0", "section": "Library", "text": "Splits Init.Data.List.Lemmas into function-specific files (#4863).", "pull request": "4863"}
{"Version": "v4.11.0", "section": "Library", "text": "Fixes statement of List.take_takeWhile (#4875).", "pull request": "4875"}
{"Version": "v4.11.0", "section": "Library", "text": "Removes 'partial' from ByteArray.toList and ByteArray.findIdx?, eliminating partial usage (#4582).", "pull request": "4582"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds recurrence theorems for bitblasting multiplication on BitVec (#4568).", "pull request": "4568"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds shiftLeftRec lemmas for BitVec (#4571).", "pull request": "4571"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds ushiftRightRec and lemmas for BitVec (#4872).", "pull request": "4872"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds getLsb_replicate for BitVec (#4873).", "pull request": "4873"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds Std.HashMap as a verified replacement for Lean.HashMap, with rename from remove to erase (#4583).", "pull request": "4583"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds Inhabited instances for new Std.HashMap (#4682).", "pull request": "4682"}
{"Version": "v4.11.0", "section": "Library", "text": "Improves BEq argument order in Std.HashMap lemmas (#4732).", "pull request": "4732"}
{"Version": "v4.11.0", "section": "Library", "text": "Makes lemmas resolve instances via unification in Std.HashMap (#4759).", "pull request": "4759"}
{"Version": "v4.11.0", "section": "Library", "text": "Documents that HashMap usage should be linear to avoid expensive copies (#4771).", "pull request": "4771"}
{"Version": "v4.11.0", "section": "Library", "text": "Removes 'bif' from HashMap lemmas (#4791).", "pull request": "4791"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds more lemmas for Std.HashMap (#4803).", "pull request": "4803"}
{"Version": "v4.11.0", "section": "Library", "text": "Upstreams SMap.foldM (#4690).", "pull request": "4690"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds PartialEquivBEq, ReflBEq, EquivBEq, LawfulHashable classes (#4607).", "pull request": "4607"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds IO.Process.Child.tryWait (#4660).", "pull request": "4660"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds ×' syntax for PProd and a delaborator for PProd/MProd to print as angle-bracket tuples (#4747, #4730, #4756).", "pull request": "4747"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds lemmas for cond (#4604).", "pull request": "4604"}
{"Version": "v4.11.0", "section": "Library", "text": "Changes some definitions into theorems (#4619).", "pull request": "4619"}
{"Version": "v4.11.0", "section": "Library", "text": "Fixes some names with duplicated namespaces (#4616).", "pull request": "4616"}
{"Version": "v4.11.0", "section": "Library", "text": "Fixes simp lemmas flagged by the simpNF linter (#4620).", "pull request": "4620"}
{"Version": "v4.11.0", "section": "Library", "text": "Makes the Antisymm class be a Prop (#4666).", "pull request": "4666"}
{"Version": "v4.11.0", "section": "Library", "text": "Cleans up unused arguments flagged by linter (#4621).", "pull request": "4621"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds imports for orphaned Init modules (#4680).", "pull request": "4680"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds imports for orphaned Std.Data modules (#4679).", "pull request": "4679"}
{"Version": "v4.11.0", "section": "Library", "text": "Adds forward/backward directions of not_exists (#4688).", "pull request": "4688"}
{"Version": "v4.11.0", "section": "Library", "text": "Upstreams eq_iff_true_of_subsingleton (#4689).", "pull request": "4689"}
{"Version": "v4.11.0", "section": "Library", "text": "Fixes precedence handling for Repr negative numbers on Int/Float (#4709).", "pull request": "4709"}
{"Version": "v4.11.0", "section": "Library", "text": "Renames TC (transitive closure) to Relation.TransGen (#4760).", "pull request": "4760"}
{"Version": "v4.11.0", "section": "Library", "text": "Fixes List deprecations (#4842).", "pull request": "4842"}
{"Version": "v4.11.0", "section": "Library", "text": "Upstreams some Mathlib attributes (#4852).", "pull request": "4852"}
{"Version": "v4.11.0", "section": "Library", "text": "Improves a proof (#93ac63).", "pull request": "93ac63"}
{"Version": "v4.11.0", "section": "Library", "text": "Generalizes universe for PSigma.exists, renames to Exists.of_psigma_prop (#4862, #4878).", "pull request": "4862"}
{"Version": "v4.11.0", "section": "Library", "text": "Fixes typos (#4737, #7d2155) and updates docs (#4782, #4869, #4648).", "pull request": "4648"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Enforces isDefEqStuckEx at unstuckMVar, providing better error messages and letting rw produce instance solutions in certain cases (#2736).", "pull request": "4596"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Fixes deprecation warnings for overloaded symbols (#4713).", "pull request": "4713"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Elab_as_elim improvements: checks that inferred motive is type-correct (#4722).", "pull request": "4722"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Elab_as_elim improvements: elaborates arguments for parameters in target types (#4800).", "pull request": "4800"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Elab_as_elim improvements: better handling for explicit motive arguments (#4817).", "pull request": "4817"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Adds a term elaborator for named patterns like n@(n'+1) to detect usage outside pattern-matching contexts (#4792).", "pull request": "4792"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Makes anonymous dot notation work with pi-type-valued type synonyms (#4818).", "pull request": "4818"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "SynthAppInstances improved for rewriting/apply tactics, adding a loop for complex instance ordering (#4646).", "pull request": "4646"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Refactors InductiveVal: isNested -> numNested (#4684, also backported as 98ee78). Modifies kernel representation of inductives.", "pull request": "4684"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Improves performance of Replacement.apply (#4776).", "pull request": "4776"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Fixes .eq_def theorem generation with messy universes (#4712).", "pull request": "4712"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Improves transformation match for IndPredBelow by better finding T.below x (#4841).", "pull request": "4841"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Kernel diagnostics appear if diagnostics is enabled, even if it is the only section (#4611).", "pull request": "4611"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Adds missing profileitM functions (#4753).", "pull request": "4753"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Adds Lean.Expr.numObjs for counting allocated sub-expressions (#4754).", "pull request": "4754"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Adds missing withTraceNodes for trace.profiler (#4769).", "pull request": "4769"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Makes 'use set_option diagnostics true' message conditional on the setting (#4781, #4882).", "pull request": "4781"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Makes 'use set_option diagnostics true' message conditional on the setting (#4781, #4882).", "pull request": "4882"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Adds ShareCommon.shareCommon' (and other related improvements) for common subterm sharing. In large expressions, up to 20x speedup (#4767, #4775, #4887).", "pull request": "4767"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Ensures Expr.replaceExpr preserves DAG structure (#4779).", "pull request": "4779"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Documents performance issues in Expr.replaceExpr (#4783).", "pull request": "4783"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Makes for_each use a precise cache (#4794, #4797, #4798).", "pull request": "4794"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Makes Expr.find?/findExt? use kernel implementations for better caching (#4795).", "pull request": "4795"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Makes Expr.replace use kernel implementation (#4799).", "pull request": "4799"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Makes Expr.foldConsts use a precise cache (#4871).", "pull request": "4871"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Makes expr_eq_fn use a precise cache (#4890).", "pull request": "4890"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Upstreams ToExpr FilePath and compile_time_search_path% (#4453).", "pull request": "4453"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Fixes handling of const2ModIdx in finalizeImport, preferring the original module for a re-declared declaration (#4652).", "pull request": "4652"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Kernel: prevents large Nat exponentiations from evaluating, gate-limited by exponentiation.threshold (#4637).", "pull request": "4637"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Updates comments in kernel/declaration.h (#4683).", "pull request": "4683"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Improves performance by using precise replace for sub-expressions (#4796).", "pull request": "4796"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Fixes expression copying overhead (10% runtime) by proper move constructor usage (#4700).", "pull request": "4700"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Speeds up replace_rec_fn::apply by avoiding expression copies (#4702).", "pull request": "4702"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Fixes a typo in constants and trace.profiler.useHeartbeats (#4590).", "pull request": "4590"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Adds 'since' dates to deprecated attributes (#4617).", "pull request": "4617"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Improves constructor-as-variable test (#4625).", "pull request": "4625"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Extends a test with example from Zulip (#4740).", "pull request": "4740"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Moves Syntax.hasIdent earlier, shakes dependencies (#4766).", "pull request": "4766"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Splits out Lean.Language.Lean.Types (#4881).", "pull request": "4881"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Adds LEAN_EXPORT for sharecommon functions (#4893).", "pull request": "4893"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Fixes typos (#4635, #4719, #af40e6).", "pull request": "4635"}
{"Version": "v4.11.0", "section": "Lean internals", "text": "Docs: Command.Scope (#4748).", "pull request": "4748"}
{"Version": "v4.11.0", "section": "Compiler, runtime, and FFI", "text": "Moves Std from libleanshared to libInit_shared, fixing Windows build (#4661).", "pull request": "4661"}
{"Version": "v4.11.0", "section": "Compiler, runtime, and FFI", "text": "Fixes initialization by explicitly calling lean_initialize for Std (#4668).", "pull request": "4668"}
{"Version": "v4.11.0", "section": "Compiler, runtime, and FFI", "text": "Adjusts shouldExport to exclude more symbols to get below Windows symbol limit (#4746). Adds partial reversions (#4884, #4956) for Verso support.", "pull request": "4746"}
{"Version": "v4.11.0", "section": "Compiler, runtime, and FFI", "text": "Adjusts shouldExport exceptions for Verso (#4884).", "pull request": "4884"}
{"Version": "v4.11.0", "section": "Compiler, runtime, and FFI", "text": "Adds lean_is_exclusive_obj (Lean.isExclusiveUnsafe) and lean_set_external_data (#4778).", "pull request": "4778"}
{"Version": "v4.11.0", "section": "Compiler, runtime, and FFI", "text": "Fixes calling programs with spaces on Windows (#4515).", "pull request": "4515"}
{"Version": "v4.11.0", "section": "Lake", "text": "Improves Git checkouts and cloud releases. On error, Lake prints all top-level logs. Forcibly fetches tags. Better error messages. The builtin package facets release, optRelease, extraDep are now consistent. Also supports optional jobs that do not fail the build. afterReleaseSync/afterReleaseAsync now fetch optRelease. See PR (#4735).", "pull request": "4735"}
{"Version": "v4.11.0", "section": "Lake", "text": "Adds draft CI workflow on new projects (#4608).", "pull request": "4608"}
{"Version": "v4.11.0", "section": "Lake", "text": "Adds CLI options --log-level and --fail-level to control log printing and build failure triggers (#4847).", "pull request": "4847"}
{"Version": "v4.11.0", "section": "Lake", "text": "Lake docs (#4853).", "pull request": "4853"}
{"Version": "v4.11.0", "section": "DevOps/CI", "text": "Release triggers update of release.lean-lang.org (#4531).", "pull request": "4531"}
{"Version": "v4.11.0", "section": "DevOps/CI", "text": "Adjusts pr-release for new lakefile.lean (#4598).", "pull request": "4598"}
{"Version": "v4.11.0", "section": "DevOps/CI", "text": "Makes pr-release use correct tag name (#4632).", "pull request": "4632"}
{"Version": "v4.11.0", "section": "DevOps/CI", "text": "Allows manual triggering of nightly release (#4638).", "pull request": "4638"}
{"Version": "v4.11.0", "section": "DevOps/CI", "text": "Adds debug output for restart-on-label (#4640). Bumps wait from 10s to 30s (#4663). Updates actions version (#4664, #582d6e).", "pull request": "4640"}
{"Version": "v4.11.0", "section": "DevOps/CI", "text": "Bumps download-artifact to 582d6e. Adds back check-stage3 (6d9718). Adds Jira sync for FRO (0768ad).", "pull request": "582d6e"}
{"Version": "v4.11.0", "section": "DevOps/CI", "text": "Adds support for reporting CI errors on FRO Zulip (#4830).", "pull request": "4830"}
{"Version": "v4.11.0", "section": "DevOps/CI", "text": "Adds nightly_bump_toolchain trigger on mathlib4 (#4838).", "pull request": "4838"}
{"Version": "v4.11.0", "section": "DevOps/CI", "text": "Fixes msys2 (#abf420).", "pull request": "abf420"}
{"Version": "v4.11.0", "section": "DevOps/CI", "text": "Deprecates Nix-based builds, removing interactive components (#4895).", "pull request": "4895"}
{"Version": "v4.11.0", "section": "DevOps/CI", "text": "Updates release checklist (#4693, #4458, #4876).", "pull request": "4693"}
{"Version": "v4.11.0", "section": "DevOps/CI", "text": "Fixes 'max dynamic symbols' metric per static library (#4669).", "pull request": "4669"}
{"Version": "v4.11.0", "section": "DevOps/CI", "text": "Improves tests/list_simp for retesting normal forms with Mathlib (#4691).", "pull request": "4691"}
{"Version": "v4.11.0", "section": "DevOps/CI", "text": "Updates the quickstart guide (#4806).", "pull request": "4806"}
{"Version": "v4.11.0", "section": "DevOps/CI", "text": "Documents triage team in the contribution guide (c02aa9).", "pull request": "c02aa9"}
{"Version": "v4.11.0", "section": "Breaking changes", "text": "For @[ext]-generated ext/ext_iff lemmas, the x and y arguments are now implicit, and these lemmas are protected. (#4543).", "pull request": "4543"}
{"Version": "v4.11.0", "section": "Breaking changes", "text": "trace.profiler.useHearbeats is now trace.profiler.useHeartbeats (#4590).", "pull request": "4590"}
{"Version": "v4.11.0", "section": "Breaking changes", "text": "A bugfix in structural recursion may break existing code if a parameter is behind indices in the recursive argument. Reordering parameters can fix it (#4672).", "pull request": "4672"}
{"Version": "v4.11.0", "section": "Breaking changes", "text": "List.filterMapM now sequences monadic actions left-to-right (#4820).", "pull request": "4820"}
{"Version": "v4.11.0", "section": "Breaking changes", "text": "The effect of the variable command on theorem bodies changed. Section variables are no longer included based on usage inside proofs; only the theorem signature, includes, or instance implicits referencing included variables cause them to be included. This ensures theorem statements do not change if the proof changes. For porting, set_option deprecated.oldSectionVars true can revert to old behavior (#4883 etc.).", "pull request": "N/A"}
{"Version": "v4.10.0", "section": "Language features, tactics, and metaprograms", "text": "Improves the strategy split uses to generalize discriminants of matches and adds trace.split.failure trace class for diagnosing issues.", "pull request": "4401"}
{"Version": "v4.10.0", "section": "Language features, tactics, and metaprograms", "text": "Prevents the tactic from claiming pre-existing goals are new subgoals.", "pull request": "4385"}
{"Version": "v4.10.0", "section": "Language features, tactics, and metaprograms", "text": "Adds dsimprocs for if expressions (ite and dite).", "pull request": "4430"}
{"Version": "v4.10.0", "section": "Language features, tactics, and metaprograms", "text": "Improves heuristics for unfolding, where equational lemmas have priorities so more-specific lemmas are tried first before a catch-all.", "pull request": "4434"}
{"Version": "v4.10.0", "section": "Language features, tactics, and metaprograms", "text": "Fixes an issue where function-valued OfNat numeric literals would become denormalized.", "pull request": "4481"}
{"Version": "v4.10.0", "section": "Language features, tactics, and metaprograms", "text": "Fixes an issue where dsimp theorems might not apply to literals.", "pull request": "4467"}
{"Version": "v4.10.0", "section": "Language features, tactics, and metaprograms", "text": "Fixes the source position for the warning for deprecated simp arguments.", "pull request": "4484"}
{"Version": "v4.10.0", "section": "Language features, tactics, and metaprograms", "text": "Adds docstrings for dsimp configuration.", "pull request": "4258"}
{"Version": "v4.10.0", "section": "Language features, tactics, and metaprograms", "text": "Improves the accuracy of used simp lemmas reported by simp?.", "pull request": "4567"}
{"Version": "v4.10.0", "section": "Language features, tactics, and metaprograms", "text": "Makes the omega tactic generate error messages lazily, improving performance when used in tactic combinators.", "pull request": "4360"}
{"Version": "v4.10.0", "section": "Language features, tactics, and metaprograms", "text": "Works around changes to the definition of Fin.sub in bv_omega tactic.", "pull request": "4579"}
{"Version": "v4.10.0", "section": "Language features, tactics, and metaprograms", "text": "Sets up groundwork for a tactic index in generated documentation, as there was in Lean 3. See PR description for details.", "pull request": "4490"}
{"Version": "v4.10.0", "section": "Commands", "text": "Makes the variable command fully elaborate binders during validation, fixing an issue where some errors would be reported only at the next declaration.", "pull request": "4370"}
{"Version": "v4.10.0", "section": "Commands", "text": "Fixes a discrepancy in universe parameter order between theorem and def declarations.", "pull request": "4408"}
{"Version": "v4.10.0", "section": "Commands", "text": "Fixes a discrepancy in the elaborators for theorem, def, and example, making Prop-valued examples and other definition commands elaborate like theorems.", "pull request": "4493"}
{"Version": "v4.10.0", "section": "Commands", "text": "Fixes a discrepancy in the elaborators for theorem, def, and example, making Prop-valued examples and other definition commands elaborate like theorems.", "pull request": "4482"}
{"Version": "v4.10.0", "section": "Commands", "text": "Fixes an elaboration bug in #check_tactic.", "pull request": "4489"}
{"Version": "v4.10.0", "section": "Commands", "text": "Adds support for open _root_.<namespace>.", "pull request": "4505"}
{"Version": "v4.10.0", "section": "Options", "text": "Adds the debug.byAsSorry option, which elaborates all 'by ...' terms as 'sorry'.", "pull request": "4576"}
{"Version": "v4.10.0", "section": "Language features, tactics, and metaprograms", "text": "Adds a linter to flag local variables whose names coincide with argumentless constructors of their type. The linter can be disabled with set_option linter.constructorNameAsVariable false. Also improves error messages suggesting similar valid constructor names.", "pull request": "4301"}
{"Version": "v4.10.0", "section": "Metaprogramming", "text": "Adds public Name.isInternalDetail function for filtering declarations using naming conventions for internal names.", "pull request": "4454"}
{"Version": "v4.10.0", "section": "Other fixes or improvements", "text": "Sorts the output of #print axioms for determinism.", "pull request": "4416"}
{"Version": "v4.10.0", "section": "Other fixes or improvements", "text": "Fixes error message range for the cdot focusing tactic.", "pull request": "4528"}
{"Version": "v4.10.0", "section": "Language server, widgets, and IDE extensions", "text": "Makes the watchdog be more resilient against badly behaving clients.", "pull request": "4443"}
{"Version": "v4.10.0", "section": "Pretty printing", "text": "Restores fallback pretty printers when context is not available, and documents addMessageContext.", "pull request": "4433"}
{"Version": "v4.10.0", "section": "Pretty printing", "text": "Introduces pp.maxSteps option and sets the default value of pp.deepTerms to false, to keep excessively large or deep terms from overwhelming the Infoview.", "pull request": "4556"}
{"Version": "v4.10.0", "section": "Library", "text": "Splits GetElem class into GetElem and GetElem? to remove Decidable instance arguments from getElem? and getElem!, improving rewritability.", "pull request": "4560"}
{"Version": "v4.10.0", "section": "Library", "text": "Makes Array.toArrayAux_eq be a simp lemma.", "pull request": "4389"}
{"Version": "v4.10.0", "section": "Library", "text": "Improves robustness of the proof for Array.reverse_data.", "pull request": "4399"}
{"Version": "v4.10.0", "section": "Library", "text": "Improves the organization of the List API.", "pull request": "4469"}
{"Version": "v4.10.0", "section": "Library", "text": "Further improves the organization of the List API.", "pull request": "4475"}
{"Version": "v4.10.0", "section": "Library", "text": "Improves the List.set and List.concat API.", "pull request": "4470"}
{"Version": "v4.10.0", "section": "Library", "text": "Upstreams lemmas about List.filter from Batteries.", "pull request": "4472"}
{"Version": "v4.10.0", "section": "Library", "text": "Adjusts @[simp] attributes for List.", "pull request": "4473"}
{"Version": "v4.10.0", "section": "Library", "text": "Makes List.getElem?_eq_getElem be a simp lemma.", "pull request": "4488"}
{"Version": "v4.10.0", "section": "Library", "text": "Adds missing List.replicate API.", "pull request": "4487"}
{"Version": "v4.10.0", "section": "Library", "text": "Adds lemmas about List.map.", "pull request": "4521"}
{"Version": "v4.10.0", "section": "Library", "text": "Changes List.length_cons to use as.length + 1 instead of as.length.succ.", "pull request": "4500"}
{"Version": "v4.10.0", "section": "Library", "text": "Fixes the statement of List.filter_congr.", "pull request": "4524"}
{"Version": "v4.10.0", "section": "Library", "text": "Changes binder explicitness in List.bind_map.", "pull request": "4525"}
{"Version": "v4.10.0", "section": "Library", "text": "Adds maximum?_eq_some_iff' and minimum?_eq_some_iff?.", "pull request": "4550"}
{"Version": "v4.10.0", "section": "Library", "text": "Switches the normal forms for indexing List and Array to xs[n] and xs[n]? rather than using List.get or Array.get.", "pull request": "4400"}
{"Version": "v4.10.0", "section": "Library", "text": "Fixes linearity in HashMap.insert and HashMap.erase, leading to a 40% speedup in a replace-heavy workload.", "pull request": "4372"}
{"Version": "v4.10.0", "section": "Library", "text": "Generalizes type of Option.forM from Unit to PUnit.", "pull request": "4403"}
{"Version": "v4.10.0", "section": "Library", "text": "Removes simp attribute from Option.elim and adds it to individual reduction lemmas, making unfolding less aggressive.", "pull request": "4504"}
{"Version": "v4.10.0", "section": "Library", "text": "Adds missing theorems for n + 1 and n - 1 normal forms.", "pull request": "4242"}
{"Version": "v4.10.0", "section": "Library", "text": "Makes Nat.min_assoc be a simp lemma.", "pull request": "4486"}
{"Version": "v4.10.0", "section": "Library", "text": "Moves @[simp] from Nat.pred_le to Nat.sub_one_le.", "pull request": "4522"}
{"Version": "v4.10.0", "section": "Library", "text": "Changes various Nat.succ n to n + 1.", "pull request": "4532"}
{"Version": "v4.10.0", "section": "Library", "text": "Adds complete div/mod simprocs for Int.", "pull request": "3850"}
{"Version": "v4.10.0", "section": "Library", "text": "Makes the byte-size interface be Nat-valued with Char.utf8Size and String.utf8ByteSize, replacing Char.csize.", "pull request": "4357"}
{"Version": "v4.10.0", "section": "Library", "text": "Upstreams Char.ext from Batteries and adds some Char documentation to the manual.", "pull request": "4438"}
{"Version": "v4.10.0", "section": "Library", "text": "Adjusts Fin.sub to be more performant in definitional equality checks.", "pull request": "4421"}
{"Version": "v4.10.0", "section": "Library", "text": "Adds missing Prod.map lemmas.", "pull request": "4526"}
{"Version": "v4.10.0", "section": "Library", "text": "Fixes binder explicitness in Prod lemmas.", "pull request": "4533"}
{"Version": "v4.10.0", "section": "Library", "text": "Adds missing simproc for BitVec equality.", "pull request": "4428"}
{"Version": "v4.10.0", "section": "Library", "text": "Adds BitVec.twoPow and lemmas, toward bitblasting multiplication for LeanSAT.", "pull request": "4417"}
{"Version": "v4.10.0", "section": "Library", "text": "Introduces Std, a library situated between Init and Lean, providing functionality not in the prelude both to Lean's implementation and to external users.", "pull request": "4499"}
{"Version": "v4.10.0", "section": "Library", "text": "Standardizes on using (· == a) over (a == ·).", "pull request": "3056"}
{"Version": "v4.10.0", "section": "Library", "text": "Fixes errors found by running the library through the Batteries linters.", "pull request": "4502"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Makes getBitVecValue? recognize BitVec.ofNatLt.", "pull request": "4391"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Adjusts instantiateMVars algorithm to zeta-reduce let expressions while beta reducing instantiated metavariables.", "pull request": "4410"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Fixes occurs check for metavariable assignments to also take metavariable types into account.", "pull request": "4420"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Fixes forEachModuleInDir to iterate over each Lean file exactly once.", "pull request": "4425"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Adds support to build Lean core oleans using Lake.", "pull request": "3886"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Improves performance of isDefEq by eta reducing lambda-abstracted terms during metavariable assignments, since they're beta reduced anyway at instantiation.", "pull request": "4387"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Removes redundant code in isDefEqQuickOther.", "pull request": "4388"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Fixes handling of metavariables when caching results at synthInstance?.", "pull request": "4530"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Makes 'don't know how to synthesize implicit argument' errors more reliably report the argument name.", "pull request": "4426"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Fixes a name resolution bug for generalized field notation (dot notation).", "pull request": "4497"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Blocks the implicit lambda feature for (e :) notation.", "pull request": "4536"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Makes it an error for there to be two functions with the same name in a where/let rec block.", "pull request": "4562"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Refactors findRecArg, extracting withRecArgInfo. Errors are now reported in parameter order rather than the order tried, and for each argument it reports why it wasn't suitable.", "pull request": "4549"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Refactors constructions toward a future port to Lean.", "pull request": "4474"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Ports mk_definition_inferring_unsafe to Lean.", "pull request": "4498"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Ports recOn construction to Lean.", "pull request": "4516"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Ports below and brecOn construction to Lean.", "pull request": "4517"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Ports below and brecOn construction to Lean.", "pull request": "4653"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Ports below and brecOn construction to Lean.", "pull request": "4651"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Adds a more-detailed docstring for PersistentEnvExtension.", "pull request": "4501"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Removes @[inline] from NameMap.find?, which caused repeated respecialization at call sites.", "pull request": "4382"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Removes the 'you might need to open '{dir}' in your editor' message, now handled by Lake and the VS Code extension.", "pull request": "4424"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Improves the performance of CollectMVars and FindMVar.", "pull request": "4451"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Adds missing DecidableEq and Repr instances for intermediate structures used by the BitVec and Fin simprocs.", "pull request": "4479"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Adds tests for a previous isDefEq issue.", "pull request": "4492"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Fixes @[implemented_by] for functions defined by well-founded recursion.", "pull request": "4508"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Adds additional tests for apply? tactic.", "pull request": "4509"}
{"Version": "v4.10.0", "section": "Lean internals", "text": "Adds a workaround for a bug in IndPredBelow.mkBelowMatcher.", "pull request": "4563"}
{"Version": "v4.10.0", "section": "Cleanup", "text": "Minor cleanup.", "pull request": "4380"}
{"Version": "v4.10.0", "section": "Compiler, runtime, and FFI", "text": "Adds validation of UTF-8 at the C++-to-Lean boundary in the runtime.", "pull request": "3963"}
{"Version": "v4.10.0", "section": "Compiler, runtime, and FFI", "text": "Fixes missing unboxing in interpreter when loading initialized value.", "pull request": "4512"}
{"Version": "v4.10.0", "section": "Compiler, runtime, and FFI", "text": "Exposes the compiler flags for the bundled C compiler (clang).", "pull request": "4477"}
{"Version": "v4.10.0", "section": "Lake", "text": "Deprecates inputFile and replaces it with inputBinFile and inputTextFile. inputTextFile normalizes line endings, ensuring platform-independent traces.", "pull request": "4384"}
{"Version": "v4.10.0", "section": "Lake", "text": "Simplifies dependency resolution code.", "pull request": "4371"}
{"Version": "v4.10.0", "section": "Lake", "text": "Touches up the Lake configuration DSL, allowing string literals instead of identifiers for names, avoids French quotes in lake new/init templates, changes the exe template to use Main, improves the math template error if lean-toolchain fails to download, and downgrades unknown config fields from error to warning for cross-version compatibility.", "pull request": "4439"}
{"Version": "v4.10.0", "section": "Lake", "text": "Tweaks require syntax and updates docs. Now require in TOML for a package like doc-gen4 does not need French quotes.", "pull request": "4496"}
{"Version": "v4.10.0", "section": "Lake", "text": "Fixes a bug where package versions in indirect dependencies would take precedence over direct dependencies.", "pull request": "4485"}
{"Version": "v4.10.0", "section": "Lake", "text": "Fixes a bug where Lake incorrectly included the module dynamic library in a platform-independent trace.", "pull request": "4478"}
{"Version": "v4.10.0", "section": "Lake", "text": "Fixes issues with bad import errors, so a bad import in an executable no longer prevents building its root module. Also shows transitive bad import locations. The root module now respects nativeFacets.", "pull request": "4529"}
{"Version": "v4.10.0", "section": "Lake", "text": "Fixes a bug where non-identifier script names could not be entered on the CLI without French quotes.", "pull request": "4564"}
{"Version": "v4.10.0", "section": "Lake", "text": "Addresses issues with precompiled libraries, ensuring Lake no longer always precompiles the package of a module. If a module is precompiled, it now also precompiles its imports.", "pull request": "4566"}
{"Version": "v4.10.0", "section": "Lake", "text": "Adds a new type of require that fetches package metadata from a registry API endpoint (like Reservoir) and then clones a Git package. This helps Lake pick the correct default branch if it's not 'master'.", "pull request": "4495"}
{"Version": "v4.10.0", "section": "Lake", "text": "Adds new type of registry-based require, improving how Lake fetches metadata from endpoints like Reservoir for packages with non-'master' default branches.", "pull request": "4692"}
{"Version": "v4.10.0", "section": "Lake", "text": "Further improves the new registry require feature, letting Lake handle the RESERVIOR_API_URL environment variable for alternative registry endpoints.", "pull request": "4849"}
{"Version": "v4.10.0", "section": "DevOps/CI", "text": "Uses Namespace runners for CI for leanprover/lean4.", "pull request": "4427"}
{"Version": "v4.10.0", "section": "DevOps/CI", "text": "Fixes speedcenter tests in CI.", "pull request": "4440"}
{"Version": "v4.10.0", "section": "DevOps/CI", "text": "Fixes that a workflow change would break CI for unrebased PRs.", "pull request": "4441"}
{"Version": "v4.10.0", "section": "DevOps/CI", "text": "Fixes Wasm release-ci.", "pull request": "4442"}
{"Version": "v4.10.0", "section": "DevOps/CI", "text": "Causes releases to be marked as prerelease on GitHub.", "pull request": "4544"}
{"Version": "v4.10.0", "section": "DevOps/CI", "text": "Switches Lake to using src/lake/lakefile.toml to avoid needing to load a version of Lake to build Lake.", "pull request": "4446"}
{"Version": "v4.10.0", "section": "Nix", "text": "Adds gdb to the Nix shell.", "pull request": "4476"}
{"Version": "v4.10.0", "section": "Nix", "text": "Adds a platform-dependent flag to the lib target in Nix builds.", "pull request": "3811"}
{"Version": "v4.10.0", "section": "Nix", "text": "Links -lStd back into Nix build flags on Darwin, fixing a build issue.", "pull request": "4587"}
{"Version": "v4.9.0", "section": "Language features, tactics, and metaprograms", "text": "Adds the seal and unseal commands, which make definitions locally irreducible or semireducible.", "pull request": "4053"}
{"Version": "v4.9.0", "section": "Language features, tactics, and metaprograms", "text": "Marks functions defined by well-founded recursion with @[irreducible] by default, preventing expensive unfolding.", "pull request": "4061"}
{"Version": "v4.9.0", "section": "Incrementality", "text": "Extends incremental elaboration into definition headers, bodies, and tactics.", "pull request": "3940"}
{"Version": "v4.9.0", "section": "Incrementality", "text": "Improves resilience by ensuring incremental commands and tactics are only reached in supported ways.", "pull request": "4259"}
{"Version": "v4.9.0", "section": "Incrementality", "text": "Adds special handling for := by so that stray tokens in tactic blocks do not inhibit incrementality.", "pull request": "4268"}
{"Version": "v4.9.0", "section": "Incrementality", "text": "Adds incremental have tactic.", "pull request": "4308"}
{"Version": "v4.9.0", "section": "Incrementality", "text": "Fixes incorrect info tree reuse with incremental elaboration.", "pull request": "4340"}
{"Version": "v4.9.0", "section": "Incrementality", "text": "Adds incrementality for careful command macros such as set_option in theorem, theorem foo.bar, and lemma.", "pull request": "4364"}
{"Version": "v4.9.0", "section": "Incrementality", "text": "Adds a conservative fix for whitespace handling to avoid incremental reuse showing goals in front of the cursor.", "pull request": "4395"}
{"Version": "v4.9.0", "section": "Incrementality", "text": "Fixes non-incremental commands in macros blocking further incremental reporting.", "pull request": "4407"}
{"Version": "v4.9.0", "section": "Incrementality", "text": "Fixes incremental reporting when there are nested tactics in terms.", "pull request": "4436"}
{"Version": "v4.9.0", "section": "Incrementality", "text": "Adds incrementality support for next and if tactics.", "pull request": "4459"}
{"Version": "v4.9.0", "section": "Incrementality", "text": "Disables incrementality for tactics-in-terms-in-tactics.", "pull request": "4554"}
{"Version": "v4.9.0", "section": "Language features, tactics, and metaprograms", "text": "Ensures that the names used for functional induction are reserved.", "pull request": "4135"}
{"Version": "v4.9.0", "section": "Language features, tactics, and metaprograms", "text": "Adds support for structural recursion on reflexive types (example: Many α).", "pull request": "4327"}
{"Version": "v4.9.0", "section": "Language features, tactics, and metaprograms", "text": "Normalizes all line endings to LF before processing, making Lean insensitive to CRLF vs LF.", "pull request": "3903"}
{"Version": "v4.9.0", "section": "Language features, tactics, and metaprograms", "text": "Makes the tactic framework able to recover from runtime errors like deterministic timeouts or max recursion depth.", "pull request": "4130"}
{"Version": "v4.9.0", "section": "split tactic", "text": "Fixes split at h when h has forward dependencies.", "pull request": "4211"}
{"Version": "v4.9.0", "section": "split tactic", "text": "Allows split for if-expressions to work on non-propositional goals.", "pull request": "4349"}
{"Version": "v4.9.0", "section": "apply tactic", "text": "Improves error messages by displaying implicit arguments in unification errors as needed (MessageData changes).", "pull request": "3929"}
{"Version": "v4.9.0", "section": "cases tactic", "text": "Adds support for unifying large offsets like x + 20000 = 20001.", "pull request": "4224"}
{"Version": "v4.9.0", "section": "omega tactic", "text": "Lets omega fall back to classical Decidable instances for contradiction proofs.", "pull request": "4073"}
{"Version": "v4.9.0", "section": "omega tactic", "text": "Fixes a bug in omega tactic.", "pull request": "4141"}
{"Version": "v4.9.0", "section": "omega tactic", "text": "Fixes another bug in omega tactic.", "pull request": "4184"}
{"Version": "v4.9.0", "section": "omega tactic", "text": "Improves the error message if no facts are found in the local context.", "pull request": "4264"}
{"Version": "v4.9.0", "section": "omega tactic", "text": "Improves expression matching by using match_expr.", "pull request": "4358"}
{"Version": "v4.9.0", "section": "simp tactic", "text": "Makes names of erased lemmas clickable.", "pull request": "4176"}
{"Version": "v4.9.0", "section": "simp tactic", "text": "Adds a pretty printer for discrimination tree keys.", "pull request": "4208"}
{"Version": "v4.9.0", "section": "simp tactic", "text": "Adds Simp.Config.index option to control discrimination tree usage, with diagnostics for 'bad keys'.", "pull request": "4202"}
{"Version": "v4.9.0", "section": "simp tactic", "text": "Prevents internal match equational theorems from appearing in simp trace.", "pull request": "4274"}
{"Version": "v4.9.0", "section": "simp tactic", "text": "Continues the simp process even if a lemma fails to elaborate, in recovery mode.", "pull request": "4177"}
{"Version": "v4.9.0", "section": "simp tactic", "text": "Continues the simp process even if a lemma fails to elaborate, in recovery mode.", "pull request": "4359"}
{"Version": "v4.9.0", "section": "simp tactic", "text": "Fixes panic when applying @[simp] to malformed theorem syntax.", "pull request": "4341"}
{"Version": "v4.9.0", "section": "simp tactic", "text": "Prevents simp from using the forward version of user-specified backward theorems.", "pull request": "4345"}
{"Version": "v4.9.0", "section": "simp tactic", "text": "Adds missing dsimp simplifications for fixed parameters in generated congruence theorems.", "pull request": "4352"}
{"Version": "v4.9.0", "section": "simp tactic", "text": "Improves trace messages for simp so constants are hoverable.", "pull request": "4362"}
{"Version": "v4.9.0", "section": "Elaboration", "text": "Makes subst notation (he ▸ h) try rewriting in both directions even with no expected type.", "pull request": "4046"}
{"Version": "v4.9.0", "section": "Elaboration", "text": "Adds support for identifiers in autoparams, e.g. (h : x = y := by exact rfl).", "pull request": "3328"}
{"Version": "v4.9.0", "section": "Elaboration", "text": "Changes how the type in let/have is elaborated, requiring tactics in the type to be fully evaluated first.", "pull request": "4096"}
{"Version": "v4.9.0", "section": "Elaboration", "text": "Ensures expression tree elaborator commits to the computed \"max type\" for arithmetic expressions.", "pull request": "4215"}
{"Version": "v4.9.0", "section": "Elaboration", "text": "Shows signature elaboration errors even if parse errors exist in the body.", "pull request": "4267"}
{"Version": "v4.9.0", "section": "Elaboration", "text": "Improves error messages when numeric literals fail to synthesize OfNat, including warnings about proposition types.", "pull request": "4368"}
{"Version": "v4.9.0", "section": "Elaboration", "text": "Fixes nested error messages/infotrees vanishing (snapshot subtrees not restored).", "pull request": "4643"}
{"Version": "v4.9.0", "section": "Elaboration", "text": "Calculates error suppression per snapshot, letting elaboration errors appear even if there are later parse errors.", "pull request": "4657"}
{"Version": "v4.9.0", "section": "Metaprogramming", "text": "Adds Lean.MVarId.revertAll to revert all free variables.", "pull request": "4167"}
{"Version": "v4.9.0", "section": "Metaprogramming", "text": "Adds Lean.MVarId.ensureNoMVar to ensure the goal's target has no expression metavariables.", "pull request": "4169"}
{"Version": "v4.9.0", "section": "Metaprogramming", "text": "Adds cleanupAnnotations parameter to forallTelescope methods.", "pull request": "4180"}
{"Version": "v4.9.0", "section": "Metaprogramming", "text": "Adds support for parser aliases in syntax quotations.", "pull request": "4307"}
{"Version": "v4.9.0", "section": "Work toward implementing grind tactic", "text": "Adds grind_norm and grind_norm_proc attributes and @[grind_norm] theorems.", "pull request": "4164"}
{"Version": "v4.9.0", "section": "Work toward implementing grind tactic", "text": "Creates grind preprocessor and core module.", "pull request": "4170"}
{"Version": "v4.9.0", "section": "Work toward implementing grind tactic", "text": "Adds special cases tactic to grind along with @[grind_cases].", "pull request": "4235"}
{"Version": "v4.9.0", "section": "Work toward implementing grind tactic", "text": "Adds special injection? tactic to grind.", "pull request": "4243"}
{"Version": "v4.9.0", "section": "Other fixes or improvements", "text": "Fixes a bug in Nat.reduceLeDiff simproc.", "pull request": "4065"}
{"Version": "v4.9.0", "section": "Other fixes or improvements", "text": "Makes deprecation warnings activate even for generalized field notation.", "pull request": "3969"}
{"Version": "v4.9.0", "section": "Other fixes or improvements", "text": "Fixes sorry so that it does not activate the implicit lambda feature.", "pull request": "4132"}
{"Version": "v4.9.0", "section": "Other fixes or improvements", "text": "Fixes the case tactic so it can be used in macros, erasing macro scopes from the tag.", "pull request": "4252"}
{"Version": "v4.9.0", "section": "Other fixes or improvements", "text": "Fixes bugs in partial calc tactic when there is mdata or metavariables.", "pull request": "4335"}
{"Version": "v4.9.0", "section": "Other fixes or improvements", "text": "Makes termination_by? report each unused parameter as _.", "pull request": "4329"}
{"Version": "v4.9.0", "section": "Language server, widgets, and IDE extensions", "text": "Fixes 'Find References' when browsing core Lean sources.", "pull request": "4066"}
{"Version": "v4.9.0", "section": "Language server, widgets, and IDE extensions", "text": "Allows embedding user widgets in structured messages (companion PR in vscode-lean4#449).", "pull request": "4254"}
{"Version": "v4.9.0", "section": "Language server, widgets, and IDE extensions", "text": "Makes watchdog more resilient against badly behaving clients.", "pull request": "4445"}
{"Version": "v4.9.0", "section": "Library", "text": "Upstreams many List and Array operations and theorems from Batteries.", "pull request": "4059"}
{"Version": "v4.9.0", "section": "Library", "text": "Removes the unused Inhabited instance for Subtype.", "pull request": "4055"}
{"Version": "v4.9.0", "section": "Library", "text": "Adds dates in existing @[deprecated] attributes.", "pull request": "3967"}
{"Version": "v4.9.0", "section": "Library", "text": "Adds boilerplate Char, UInt, and Fin theorems.", "pull request": "4231"}
{"Version": "v4.9.0", "section": "Library", "text": "Fixes the MonadStore type classes to use semiOutParam.", "pull request": "4205"}
{"Version": "v4.9.0", "section": "Library", "text": "Renames IsLawfulSingleton to LawfulSingleton.", "pull request": "4350"}
{"Version": "v4.9.0", "section": "Nat", "text": "Swaps Nat.zero_or and Nat.or_zero.", "pull request": "4094"}
{"Version": "v4.9.0", "section": "Nat", "text": "Changes definition of Nat.mod so n % (m + n) reduces when n is a literal without well-founded recursion.", "pull request": "4098"}
{"Version": "v4.9.0", "section": "Nat", "text": "Changes definition of Nat.mod to avoid well-founded recursion becoming irreducible by default.", "pull request": "4145"}
{"Version": "v4.9.0", "section": "Nat", "text": "Redefines Nat.testBit to be more performant.", "pull request": "4188"}
{"Version": "v4.9.0", "section": "Nat", "text": "Adds theorems for Nat.", "pull request": "4199"}
{"Version": "v4.9.0", "section": "Array", "text": "Improves functional induction principle Array.feraseIdx.induct.", "pull request": "4074"}
{"Version": "v4.9.0", "section": "List", "text": "Removes @[simp] from List.length_pos.", "pull request": "4172"}
{"Version": "v4.9.0", "section": "Option", "text": "Adds theorems to simplify Option-valued dependent if-then-else.", "pull request": "4037"}
{"Version": "v4.9.0", "section": "Option", "text": "Removes @[simp] from Option.bind_eq_some.", "pull request": "4314"}
{"Version": "v4.9.0", "section": "BitVec", "text": "Adds theorems for BitVec.", "pull request": "4095"}
{"Version": "v4.9.0", "section": "BitVec", "text": "Adds simprocs for reducing x >>> i and x <<< i when i is a bitvector literal.", "pull request": "4193"}
{"Version": "v4.9.0", "section": "BitVec", "text": "Adds simprocs for reducing repeated shifts (x <<< i) <<< j and (x >>> i) >>> j.", "pull request": "4194"}
{"Version": "v4.9.0", "section": "BitVec", "text": "Redefines rotateLeft/rotateRight to use modulo reduction of the shift offset.", "pull request": "4229"}
{"Version": "v4.9.0", "section": "BitVec", "text": "Makes <num>#<term> bitvector literal notation global, removing <term>#<term> form.", "pull request": "0d3051 (commit)"}
{"Version": "v4.9.0", "section": "HashMap", "text": "Fixes implicitness of typeclass arguments in HashMap.ofList.", "pull request": "4248"}
{"Version": "v4.9.0", "section": "IO", "text": "Adds IO.Process.getCurrentDir and IO.Process.setCurrentDir for adjusting current working directory.", "pull request": "4036"}
{"Version": "v4.9.0", "section": "Cleanup", "text": "Minor cleanup.", "pull request": "4077"}
{"Version": "v4.9.0", "section": "Lean internals (Defeq and WHNF)", "text": "Removes unnecessary checkpointDefEq.", "pull request": "4029"}
{"Version": "v4.9.0", "section": "Lean internals (Defeq and WHNF)", "text": "Fixes isReadOnlyOrSyntheticOpaque to respect metavariable depth.", "pull request": "4206"}
{"Version": "v4.9.0", "section": "Lean internals (Defeq and WHNF)", "text": "Fixes missing occurs check for delayed assignments.", "pull request": "4217"}
{"Version": "v4.9.0", "section": "Lean internals (Definition transparency)", "text": "Adds validation for @[reducible]/@[semireducible]/@[irreducible] attributes, with local/scoped modifiers.", "pull request": "4052"}
{"Version": "v4.9.0", "section": "Lean internals (Inductive types)", "text": "Fixes a bug where indices could be incorrectly promoted to parameters.", "pull request": "3591"}
{"Version": "v4.9.0", "section": "Lean internals (Inductive types)", "text": "Fixes a bug in the injectivity theorem generator.", "pull request": "3398"}
{"Version": "v4.9.0", "section": "Lean internals (Inductive types)", "text": "Fixes elaboration of mutual inductives with instance parameters.", "pull request": "4342"}
{"Version": "v4.9.0", "section": "Lean internals (Diagnostics and profiling)", "text": "Adds option trace.profiler.useHeartbeats to measure profiler.threshold in heartbeats rather than ms.", "pull request": "3986"}
{"Version": "v4.9.0", "section": "Lean internals (Diagnostics and profiling)", "text": "Makes set_option diagnostics true report kernel diagnostic info.", "pull request": "4082"}
{"Version": "v4.9.0", "section": "Lean internals (Typeclass resolution)", "text": "Fixes multiple issues with TC caching interacting with synthPendingDepth, adds maxSynthPendingDepth = 1.", "pull request": "4119"}
{"Version": "v4.9.0", "section": "Lean internals (Typeclass resolution)", "text": "Ensures local instance cache does not contain duplicates.", "pull request": "4210"}
{"Version": "v4.9.0", "section": "Lean internals (Typeclass resolution)", "text": "Fixes handling of metavariables so that backward.synthInstance.canonInstances need not be false.", "pull request": "4216"}
{"Version": "v4.9.0", "section": "Lean internals (Other fixes)", "text": "Fixes propagation of state for liftCoreM/liftTermElabM in Lean.Elab.Command.", "pull request": "4080"}
{"Version": "v4.9.0", "section": "Lean internals (Other fixes)", "text": "Makes the Repr deriving handler consistent for structure vs inductive (erasing types/proofs).", "pull request": "3944"}
{"Version": "v4.9.0", "section": "Lean internals (Other fixes)", "text": "Propagates maxHeartbeats to the kernel, controlling (kernel) deterministic timeout errors.", "pull request": "4113"}
{"Version": "v4.9.0", "section": "Lean internals (Other fixes)", "text": "Reverts #3970 (monadic generalization of FindExpr).", "pull request": "4125"}
{"Version": "v4.9.0", "section": "Lean internals (Other fixes)", "text": "Catches stack overflow in auto-bound implicits feature.", "pull request": "4128"}
{"Version": "v4.9.0", "section": "Lean internals (Other fixes)", "text": "Adds tryCatchRuntimeEx combinator to replace catchRuntimeEx reader state.", "pull request": "4129"}
{"Version": "v4.9.0", "section": "Lean internals (Other fixes)", "text": "Simplifies the expression canonicalizer.", "pull request": "4155"}
{"Version": "v4.9.0", "section": "Lean internals (Other fixes)", "text": "Adds many missing trace classes (Elab, Tactic, etc.).", "pull request": "4151"}
{"Version": "v4.9.0", "section": "Lean internals (Other fixes)", "text": "Adds more missing trace classes.", "pull request": "4369"}
{"Version": "v4.9.0", "section": "Lean internals (Other fixes)", "text": "Makes congruence theorem generators clean up type annotations of argument types.", "pull request": "4185"}
{"Version": "v4.9.0", "section": "Lean internals (Other fixes)", "text": "Fixes restoration of infotrees with auto-bound implicits, improving hovers and variable linter accuracy.", "pull request": "4192"}
{"Version": "v4.9.0", "section": "Lean internals (Other fixes)", "text": "Fixes an issue where the interrupt exception was swallowed by some tryCatchRuntimeEx uses (merge conflict).", "pull request": "4569"}
{"Version": "v4.9.0", "section": "Lean internals (Other fixes)", "text": "Adapts kernel interruption to the new cancellation system.", "pull request": "4584"}
{"Version": "v4.9.0", "section": "Cleanup", "text": "Minor cleanup.", "pull request": "4112"}
{"Version": "v4.9.0", "section": "Compiler, runtime, and FFI", "text": "Improves reset/reuse algorithm, relaxing constraints in a second pass for memory reuse.", "pull request": "4100"}
{"Version": "v4.9.0", "section": "Compiler, runtime, and FFI", "text": "Fixes segfault in old compiler from mishandling noConfusion applications.", "pull request": "2903"}
{"Version": "v4.9.0", "section": "Compiler, runtime, and FFI", "text": "Fixes bug in constant folding in the compiler.", "pull request": "4311"}
{"Version": "v4.9.0", "section": "Compiler, runtime, and FFI", "text": "Documents the runtime memory layout for inductive types.", "pull request": "3915"}
{"Version": "v4.9.0", "section": "Lake", "text": "Makes trace reading more robust, rebuilding if trace files are invalid/unreadable. Backwards-compatible with numeric traces.", "pull request": "4518"}
{"Version": "v4.9.0", "section": "Lake", "text": "Adds support for docstrings on require commands.", "pull request": "4057"}
{"Version": "v4.9.0", "section": "Lake", "text": "Improves hovers for family_def and library_data commands.", "pull request": "4088"}
{"Version": "v4.9.0", "section": "Lake", "text": "Adds default README.md to package templates.", "pull request": "4147"}
{"Version": "v4.9.0", "section": "Lake", "text": "Extends lake test help page, adds lake lint, supports specifying test/lint drivers, library test drivers, etc.", "pull request": "4261"}
{"Version": "v4.9.0", "section": "Lake", "text": "Adds lake pack and lake unpack for archiving build artifacts.", "pull request": "4270"}
{"Version": "v4.9.0", "section": "Lake", "text": "Switches manifest format to semantic versioning, e.g. major.minor.patch with backward compatibility for older numeric versions.", "pull request": "4083"}
{"Version": "v4.9.0", "section": "Lake", "text": "Adds a lift from JobM to FetchM for backwards compatibility.", "pull request": "4273"}
{"Version": "v4.9.0", "section": "Lake", "text": "Fixes performance issues when lifting LogIO to CliM.", "pull request": "4351"}
{"Version": "v4.9.0", "section": "Lake", "text": "Makes Lake store the dependency trace in the cached build and verify it before replaying logs.", "pull request": "4343"}
{"Version": "v4.9.0", "section": "Lake", "text": "Moves the cached log into the trace file, ensuring out-of-date logs aren't associated with up-to-date traces.", "pull request": "4402"}
{"Version": "v4.9.0", "section": "Lake", "text": "Cleans up tests.", "pull request": "4056"}
{"Version": "v4.9.0", "section": "Lake", "text": "Fixes noRelease test when Lean repo is tagged.", "pull request": "4244"}
{"Version": "v4.9.0", "section": "Lake", "text": "Improves tests/serve script.", "pull request": "4346"}
{"Version": "v4.9.0", "section": "Lake", "text": "Adds build log path to the warning for missing or invalid build log.", "pull request": "4356"}
{"Version": "v4.9.0", "section": "DevOps", "text": "Adds a script (script/rebase-stage0.sh) for git rebase -i that updates each stage0 automatically.", "pull request": "3984"}
{"Version": "v4.9.0", "section": "DevOps", "text": "Finishes renamings from transition to Std to Batteries.", "pull request": "4108"}
{"Version": "v4.9.0", "section": "DevOps", "text": "Adjusts the GitHub bug template to mention testing on live.lean-lang.org.", "pull request": "4109"}
{"Version": "v4.9.0", "section": "DevOps", "text": "Makes CI rerun only when full-ci label is added or removed.", "pull request": "4136"}
{"Version": "v4.9.0", "section": "DevOps", "text": "Switches to #guard_msgs in tests wherever possible.", "pull request": "4175"}
{"Version": "v4.9.0", "section": "DevOps", "text": "Explains the Lean4 pygments lexer.", "pull request": "3125"}
{"Version": "v4.9.0", "section": "DevOps", "text": "Sets up a procedure for preparing release notes.", "pull request": "4247"}
{"Version": "v4.9.0", "section": "DevOps", "text": "Modernizes build instructions and workflows.", "pull request": "4032"}
{"Version": "v4.9.0", "section": "DevOps", "text": "Moves some expensive checks from merge queue to releases.", "pull request": "4255"}
{"Version": "v4.9.0", "section": "DevOps", "text": "Adds aarch64 macOS as a native compilation target in CI.", "pull request": "4265"}
{"Version": "v4.9.0", "section": "DevOps", "text": "Updates build instructions for macOS.", "pull request": "4317"}
{"Version": "v4.9.0", "section": "DevOps", "text": "Adjusts workflow to update Batteries in the manifest for lean-pr-testing-NNNN branches.", "pull request": "4333"}
{"Version": "v4.9.0", "section": "DevOps", "text": "Simplifies lean4checker step of the release checklist.", "pull request": "4355"}
{"Version": "v4.9.0", "section": "DevOps", "text": "Adds installing elan to pr-release CI step.", "pull request": "4361"}
{"Version": "v4.9.0", "section": "DevOps", "text": "Fixes the Windows build which was missing an exported symbol.", "pull request": "4628"}
{"Version": "v4.9.0", "section": "Breaking changes", "text": "Now well-founded recursive functions have @[irreducible], which can break definitional-equality-based proofs.", "pull request": "4061"}
{"Version": "v4.9.0", "section": "Breaking changes", "text": "Swaps Nat.zero_or and Nat.or_zero.", "pull request": "4094"}
{"Version": "v4.9.0", "section": "Breaking changes", "text": "Renames IsLawfulSingleton to LawfulSingleton.", "pull request": "4350"}
{"Version": "v4.9.0", "section": "Breaking changes", "text": "BitVec literal notation is now <num>#<term>, global, and rotateLeft/rotateRight take shift modulo bitwidth.", "pull request": "4229"}
{"Version": "v4.9.0", "section": "Breaking changes", "text": "No longer simp lemmas: List.length_pos and Option.bind_eq_some.", "pull request": "4172 / 4314"}
{"Version": "v4.9.0", "section": "Breaking changes", "text": "Due to #3929, MessageData.ofPPFormat is removed; use MessageData.lazy or .ofFormatWithInfos.", "pull request": "3929"}
{"Version": "v4.9.0", "section": "Breaking changes", "text": "Types in let/have can fail to elaborate due to new restrictions on embedded tactics (#4096).", "pull request": "4096"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Functional induction)", "text": "Introduces a functional induction principle for recursive functions.", "pull request": "3432"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Functional induction)", "text": "Expands or modifies the functional induction mechanism.", "pull request": "3620"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Functional induction)", "text": "Refines generation of functional induction theorems for certain definitions.", "pull request": "3754"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Functional induction)", "text": "Improves elaboration or usage of functional induction principles.", "pull request": "3762"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Functional induction)", "text": "Optimizes aspects of functional induction for specific patterns.", "pull request": "3738"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Functional induction)", "text": "Extends functional induction with additional features or fixes.", "pull request": "3776"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Functional induction)", "text": "Updates functional induction principle edge cases.", "pull request": "3898"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Termination checker)", "text": "Makes termination_by? avoid sizeOf when unnecessary.", "pull request": "3630"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Termination checker)", "text": "Improves the termination_by syntax.", "pull request": "3652"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Termination checker)", "text": "Changes how termination arguments are elaborated.", "pull request": "3658"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Termination checker)", "text": "Refactors GuessLex to allow more complex inferred termination arguments.", "pull request": "3665"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Termination checker)", "text": "Infers termination arguments like xs.size - i automatically.", "pull request": "3666"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Custom eliminators)", "text": "Introduces @[induction_eliminator] for custom induction tactics.", "pull request": "3629"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Custom eliminators)", "text": "Introduces @[cases_eliminator] for custom cases tactics.", "pull request": "3655"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Custom eliminators)", "text": "Provides custom Nat eliminators so 'induction' uses n+1, not Nat.succ n.", "pull request": "3747"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Shorter instance names)", "text": "Reduces generated anonymous instance name length using a new algorithm.", "pull request": "3089"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Shorter instance names)", "text": "Refines cross-project uniqueness by adding a module-based suffix.", "pull request": "3934"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (simp/dsimp)", "text": "Enables kernel projection reduction in dsimp.", "pull request": "3607"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (simp/dsimp)", "text": "Makes dsimp normalize raw Nat literals as OfNat.ofNat.", "pull request": "3624"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (simp/dsimp)", "text": "Ensures simp handles OfScientific literals properly.", "pull request": "3628"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (simp/dsimp)", "text": "Makes dsimp? report used simprocs.", "pull request": "3654"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (simp/dsimp)", "text": "Improves performance when simp encounters a loop.", "pull request": "3819"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (simp/dsimp)", "text": "Fixes discharger/cache interaction in simp.", "pull request": "3821"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (simp/dsimp)", "text": "Prevents simp from breaking Char literals.", "pull request": "3824"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (simp/dsimp)", "text": "Allows more lenient matching for Nat instances in simp.", "pull request": "3838"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (simp/dsimp)", "text": "Documents simp configuration options.", "pull request": "3870"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (simp/dsimp)", "text": "Fixes simp caching issues.", "pull request": "3972"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (simp/dsimp)", "text": "Improves cache behavior for well-behaved dischargers in simp.", "pull request": "4044"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (omega)", "text": "Introduces a term canonicalizer for omega.", "pull request": "3639"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (omega)", "text": "Improves the positivity handling for Int modulo operator.", "pull request": "3736"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (omega)", "text": "Lets omega function as a simp discharger.", "pull request": "3828"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (omega)", "text": "Adds helpful error messages for omega usage.", "pull request": "3847"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (omega)", "text": "Refines internal usage or correctness in omega tactic.", "pull request": "3766"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (omega)", "text": "Further fixes or improvements for omega logic.", "pull request": "3853"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (omega)", "text": "Enhances fallback error handling in omega tactic.", "pull request": "3875"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (rfl)", "text": "Upstreams @[refl] attribute and the rfl tactic.", "pull request": "3671"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (rfl)", "text": "Continues upstreaming rfl features or patches.", "pull request": "3708"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (rfl)", "text": "Makes apply_rfl not operate on Eq itself.", "pull request": "3751"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (rfl)", "text": "Improves rfl error message when no goals remain.", "pull request": "4067"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (rw?)", "text": "Upstreams the rw? tactic for rewriting suggestions.", "pull request": "3719"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (rw?)", "text": "Fixes or improves the rw? tactic usage details.", "pull request": "3783"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (rw?)", "text": "Additional enhancements for lemma selection in rw?.", "pull request": "3794"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (rw?)", "text": "Further refinements or fixes for rw? rewriting approach.", "pull request": "3911"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (conv)", "text": "Adds a conv version of the calc tactic.", "pull request": "3659"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (conv)", "text": "Uses try with_reducible rfl to clean up conv states.", "pull request": "3763"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (#guard_msgs)", "text": "Introduces whitespace protection with the ⏎ char in #guard_msgs.", "pull request": "3617"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (#guard_msgs)", "text": "Adds options for whitespace normalization and message ordering in #guard_msgs.", "pull request": "3883"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (#guard_msgs)", "text": "Adds an unused variables ignore function for #guard_msgs checks.", "pull request": "3931"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (#guard_msgs)", "text": "Introduces diff output comparing expected vs. actual messages (#guard_msgs.diff).", "pull request": "3912"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (do notation)", "text": "Makes it an error to lift (<- ...) out of a pure if ... then ... else.", "pull request": "3820"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (LazyDiscrTree)", "text": "Fixes a name collision for LazyDiscrTree that caused cache poisoning.", "pull request": "3610"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (LazyDiscrTree)", "text": "Simplifies exact?/apply? usage in LazyDiscrTree.", "pull request": "3677"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (LazyDiscrTree)", "text": "Moves general exact?/apply? logic into LazyDiscrTree internals.", "pull request": "3685"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (LazyDiscrTree)", "text": "Improves lemma selection for rw? using LazyDiscrTree.", "pull request": "3769"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (LazyDiscrTree)", "text": "Improves ordering of matches in LazyDiscrTree lookups.", "pull request": "3818"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms", "text": "Adds inductive.autoPromoteIndices option to disable index auto-promotion.", "pull request": "3590"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Preserves simp cache/dischargeDepth fields in Lean.Meta.Simp.Result.mkEqSymm.", "pull request": "3606"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Makes elabTermEnsuringType respect errToSorry to improve error recovery in have.", "pull request": "3633"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Allows noncomputable unsafe definitions, deferring implementations.", "pull request": "3647"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Adjusts namespaces of certain tactics for consistency.", "pull request": "3672"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Fixes Ord derive handler for indexed inductives with unused alternatives.", "pull request": "3725"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Improves performance of derived Ord instances.", "pull request": "3893"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Changes error reporting for failing tactic macros, e.g. rfl no-goal error.", "pull request": "3771"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Fixes elaboration of generalized field notation if the object is optional param.", "pull request": "3745"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Requires colGt for commands like universe, variable, namespace to avoid parse ambiguities.", "pull request": "3799"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Lets split tactic be used in code contexts, not just proofs.", "pull request": "3815"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Adds missing info for induction with with-clauses (| cstr a b => ?_).", "pull request": "3822"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Fixes withSetOptionIn combinator usage.", "pull request": "3806"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Removes unused trace.Elab.syntax option.", "pull request": "3844"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Improves hover/go-to-def for attribute command usage.", "pull request": "3896"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Makes linter options more discoverable.", "pull request": "3989"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Fixes go-to-def for syntax from @[builtin_term_parser].", "pull request": "3916"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Makes solveByElim handle symm lemmas correctly, re-enabling exact?/apply?.", "pull request": "3962"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Improves the @[deprecated] attribute to accept (since := \"<date>\").", "pull request": "3968"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Makes #print show structure fields.", "pull request": "3768"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Makes exact?% behave like by exact? rather than by apply?.", "pull request": "3974"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Forbids same transparency in decreasing_trivial macros, clarifying usage.", "pull request": "3994"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Adjusts transparency for he ▸ h notation elaboration.", "pull request": "3991"}
{"Version": "v4.8.0", "section": "Language features, tactics, and metaprograms (Misc fixes)", "text": "Speeds up binop%/binrel% expression tree elaborators.", "pull request": "4092"}
{"Version": "v4.8.0", "section": "Docs", "text": "Documentation improvements and clarifications for various Lean 4 features.", "pull request": "3748"}
{"Version": "v4.8.0", "section": "Docs", "text": "Adds or refines doc examples in the Lean codebase.", "pull request": "3796"}
{"Version": "v4.8.0", "section": "Docs", "text": "More usage examples and reference docs for Lean 4 tactics.", "pull request": "3800"}
{"Version": "v4.8.0", "section": "Docs", "text": "Documents further config and internal details of Lean 4.", "pull request": "3874"}
{"Version": "v4.8.0", "section": "Docs", "text": "Adds clarifications and usage notes for advanced Lean concepts.", "pull request": "3863"}
{"Version": "v4.8.0", "section": "Docs", "text": "Expands documentation on certain language constructs or modules.", "pull request": "3862"}
{"Version": "v4.8.0", "section": "Docs", "text": "Improves doc references for library code or syntax usage.", "pull request": "3891"}
{"Version": "v4.8.0", "section": "Docs", "text": "Refines doc strings for macros or commands.", "pull request": "3873"}
{"Version": "v4.8.0", "section": "Docs", "text": "Explains minor details in the reference about Lean code structure.", "pull request": "3908"}
{"Version": "v4.8.0", "section": "Docs", "text": "Adds a few clarifications to specialized doc topics.", "pull request": "3872"}
{"Version": "v4.8.0", "section": "Language server and IDE", "text": "Enables auto-completions for import statements in the server.", "pull request": "3602"}
{"Version": "v4.8.0", "section": "Language server and IDE", "text": "Fixes off-by-one errors in diagnostic ranges (#392 in vscode-lean4).", "pull request": "3608"}
{"Version": "v4.8.0", "section": "Language server and IDE", "text": "Introduces snapshot trees for incremental tactics/parallelism foundation.", "pull request": "3014"}
{"Version": "v4.8.0", "section": "Language server and IDE", "text": "Adds a basic incrementality API for snapshot-based elaboration.", "pull request": "3849"}
{"Version": "v4.8.0", "section": "Language server and IDE", "text": "Allows server-to-client requests for advanced IDE features.", "pull request": "3271"}
{"Version": "v4.8.0", "section": "Language server and IDE", "text": "Fixes jump to definition with conflicting names from different files (#1170).", "pull request": "3656"}
{"Version": "v4.8.0", "section": "Language server and IDE", "text": "Keeps semantic tokens in sync, improving performance of semantic highlighting.", "pull request": "3691"}
{"Version": "v4.8.0", "section": "Language server and IDE", "text": "Further optimizes or stabilizes semantic tokens usage in the LSP server.", "pull request": "3925"}
{"Version": "v4.8.0", "section": "Language server and IDE", "text": "Enhances synchronization or correctness in semantic tokens logic.", "pull request": "3932"}
{"Version": "v4.8.0", "section": "Language server and IDE", "text": "Shows diagnostics suggesting 'Restart File' when a file dependency is saved.", "pull request": "3247"}
{"Version": "v4.8.0", "section": "Language server and IDE", "text": "Adds more diagnostics for 'Restart File' usage in the server.", "pull request": "3730"}
{"Version": "v4.8.0", "section": "Language server and IDE", "text": "Uses correct module names in references or highlight output.", "pull request": "3722"}
{"Version": "v4.8.0", "section": "Language server and IDE", "text": "Makes errors in the file header appear reliably, sets 'Import out of date' warning severity as hint.", "pull request": "3728"}
{"Version": "v4.8.0", "section": "Language server and IDE", "text": "Simplifies text of 'Import out of date' warning message.", "pull request": "3739"}
{"Version": "v4.8.0", "section": "Language server and IDE", "text": "Fixes info nodes from before the cursor being used for completions (#3462).", "pull request": "3778"}
{"Version": "v4.8.0", "section": "Language server and IDE", "text": "Displays trace timings in Infoview for deeper performance insight.", "pull request": "3985"}
{"Version": "v4.8.0", "section": "Pretty printing", "text": "Fixes hovers over binders so that they show types properly.", "pull request": "3797"}
{"Version": "v4.8.0", "section": "Pretty printing", "text": "Adds attribute @[pp_using_anonymous_constructor] for structures to print as ⟨x,y,z⟩.", "pull request": "3640"}
{"Version": "v4.8.0", "section": "Pretty printing", "text": "Expands usage of @[pp_using_anonymous_constructor] on structures like Sigma/PSigma.", "pull request": "3735"}
{"Version": "v4.8.0", "section": "Pretty printing", "text": "Inlines parent-structure fields for structure instance printing by default.", "pull request": "3749"}
{"Version": "v4.8.0", "section": "Pretty printing", "text": "Renames pp.structureProjections to pp.fieldNotation, adding suboption generalized.", "pull request": "3737"}
{"Version": "v4.8.0", "section": "Pretty printing", "text": "Allows disabling or restricting field notation on a function-by-function basis.", "pull request": "3744"}
{"Version": "v4.8.0", "section": "Pretty printing", "text": "Ensures no field notation is used on theorems, only definitions or functions.", "pull request": "3750"}
{"Version": "v4.8.0", "section": "Pretty printing", "text": "Fixes interaction between app unexpanders and pp.fieldNotation.generalized.", "pull request": "4071"}
{"Version": "v4.8.0", "section": "Pretty printing", "text": "Makes delabConstWithSignature put arguments after the colon when needed.", "pull request": "3625"}
{"Version": "v4.8.0", "section": "Pretty printing", "text": "Adds option pp.mvars (default true) and pp.mvars.withType (default false).", "pull request": "3798"}
{"Version": "v4.8.0", "section": "Pretty printing", "text": "Shows expression metavariables with type info if pp.mvars.withType is true.", "pull request": "3978"}
{"Version": "v4.8.0", "section": "Pretty printing", "text": "Hides or shortens metavariable names if pp.mvars is false.", "pull request": "3980"}
{"Version": "v4.8.0", "section": "Pretty printing", "text": "Makes binders hoverable in code with docstrings displayed.", "pull request": "3917"}
{"Version": "v4.8.0", "section": "Pretty printing", "text": "Shows correct term in hovers for RHS of match expressions in Infoview.", "pull request": "4034"}
{"Version": "v4.8.0", "section": "Library (Bool/Prop)", "text": "Improves simp confluence for mixing Bool and Prop terms.", "pull request": "3508"}
{"Version": "v4.8.0", "section": "Library (Bool/Prop)", "text": "Adds more theorems or simplification rules for Bool/Prop usage.", "pull request": "3604"}
{"Version": "v4.8.0", "section": "Library (Nat)", "text": "Makes Nat.succ_eq_add_one a simp lemma, aligning with n+1 usage.", "pull request": "3579"}
{"Version": "v4.8.0", "section": "Library (Nat)", "text": "Replaces Nat.succ rules with simprocs for simpler rewriting.", "pull request": "3808"}
{"Version": "v4.8.0", "section": "Library (Nat)", "text": "Adds faster Nat.repr implementation in C.", "pull request": "3876"}
{"Version": "v4.8.0", "section": "Library (Int)", "text": "Adds or refines Int theorems for integer operations.", "pull request": "3890"}
{"Version": "v4.8.0", "section": "Library (UInt)", "text": "Improves performance of UInt upcasting operations.", "pull request": "3960"}
{"Version": "v4.8.0", "section": "Library (Array/Subarray)", "text": "Removes Array.eraseIdxAux, eraseIdxSzAux, eraseIdx'.", "pull request": "3676"}
{"Version": "v4.8.0", "section": "Library (Array/Subarray)", "text": "Simplifies Array.findIdx? implementation.", "pull request": "3648"}
{"Version": "v4.8.0", "section": "Library (Array/Subarray)", "text": "Renames Subarray fields from as/h₁/h₂ to array/start_le_stop/stop_le_array_size.", "pull request": "3851"}
{"Version": "v4.8.0", "section": "Library (List)", "text": "Upstreams tail-recursive List operations and @[csimp] lemmas.", "pull request": "3785"}
{"Version": "v4.8.0", "section": "Library (BitVec)", "text": "Adds or refines BitVec theorems for shifting/rotation, rewriting, etc.", "pull request": "3593"}
{"Version": "v4.8.0", "section": "Library (BitVec)", "text": "Further updates BitVec theorems for various operations.", "pull request": "3597"}
{"Version": "v4.8.0", "section": "Library (BitVec)", "text": "Extends BitVec rewriting rules or proofs.", "pull request": "3598"}
{"Version": "v4.8.0", "section": "Library (BitVec)", "text": "Adds additional BitVec lemmas or theorems (like rotation).", "pull request": "3721"}
{"Version": "v4.8.0", "section": "Library (BitVec)", "text": "Refines BitVec usage with advanced rewriting or equivalences.", "pull request": "3729"}
{"Version": "v4.8.0", "section": "Library (BitVec)", "text": "Provides more BitVec facts for numeric reasoning.", "pull request": "3880"}
{"Version": "v4.8.0", "section": "Library (BitVec)", "text": "Adds further expansions or corrections to BitVec theorems.", "pull request": "4039"}
{"Version": "v4.8.0", "section": "Library (BitVec)", "text": "Protects Std.BitVec to avoid undesired overshadowing or redefinition.", "pull request": "3884"}
{"Version": "v4.8.0", "section": "Library (String)", "text": "Fixes String.splitOn function behavior.", "pull request": "3832"}
{"Version": "v4.8.0", "section": "Library (String)", "text": "Adds String.Pos.isValid and UTF-8 string validation logic.", "pull request": "3959"}
{"Version": "v4.8.0", "section": "Library (String)", "text": "Implements a reference model for UTF-8 encoding/decoding in String.", "pull request": "3961"}
{"Version": "v4.8.0", "section": "Library (IO)", "text": "Adds IO.getTaskState to check a task's runtime state (finished/running/waiting).", "pull request": "4097"}
{"Version": "v4.8.0", "section": "Library (Refactors)", "text": "Reduces imports for Init.Data.Nat and Init.Data.Int.", "pull request": "3605"}
{"Version": "v4.8.0", "section": "Library (Refactors)", "text": "Reduces imports for Init.Omega.Int, making it leaner.", "pull request": "3613"}
{"Version": "v4.8.0", "section": "Library (Refactors)", "text": "Upstreams Std.Data.Nat into core Lean library.", "pull request": "3634"}
{"Version": "v4.8.0", "section": "Library (Refactors)", "text": "Upstreams Std.Data.Int into core Lean library.", "pull request": "3635"}
{"Version": "v4.8.0", "section": "Library (Refactors)", "text": "Further import reductions for omega-related modules.", "pull request": "3790"}
{"Version": "v4.8.0", "section": "Library (Refactors)", "text": "Extends GetElem interface with getElem! and getElem? for containers.", "pull request": "3694"}
{"Version": "v4.8.0", "section": "Library (Refactors)", "text": "Renames Option.toMonad to Option.getM, removing unneeded Monad argument.", "pull request": "3865"}
{"Version": "v4.8.0", "section": "Library (Refactors)", "text": "Merges lexOrd with compareLex for consistent lexicographic ordering.", "pull request": "3882"}
{"Version": "v4.8.0", "section": "Library (Other fixes/improvements)", "text": "Makes Quotient.sound a theorem instead of a definition.", "pull request": "3765"}
{"Version": "v4.8.0", "section": "Library (Other fixes/improvements)", "text": "Fixes System.FilePath.parent for absolute paths on certain platforms.", "pull request": "3645"}
{"Version": "v4.8.0", "section": "Library (Other fixes/improvements)", "text": "Corrects ByteArray.toUInt64LE!/toUInt64BE! being swapped.", "pull request": "3660"}
{"Version": "v4.8.0", "section": "Library (Other fixes/improvements)", "text": "Fixes linearity in HashMap.insertIfNew, HashSet.erase, HashMap.erase.", "pull request": "3881"}
{"Version": "v4.8.0", "section": "Library (Other fixes/improvements)", "text": "Further linearity fix for certain HashSet or HashMap operations.", "pull request": "3887"}
{"Version": "v4.8.0", "section": "Library (Other fixes/improvements)", "text": "Ensures linearity in Parsec.many*Core loops.", "pull request": "3830"}
{"Version": "v4.8.0", "section": "Library (Other fixes/improvements)", "text": "Adds FS.Stream.isTty field for checking TTY state in streams.", "pull request": "3930"}
{"Version": "v4.8.0", "section": "Library (Other fixes/improvements)", "text": "Deprecates Option.toBool in favor of Option.isSome.", "pull request": "3866"}
{"Version": "v4.8.0", "section": "Library (Other fixes/improvements)", "text": "Upstreams Data.List.Init and Data.Array.Init from Std.", "pull request": "3975"}
{"Version": "v4.8.0", "section": "Library (Other fixes/improvements)", "text": "Adds instances so ac_rfl can work without Mathlib.", "pull request": "3942"}
{"Version": "v4.8.0", "section": "Library (Other fixes/improvements)", "text": "Changes Fin.induction to use structural induction for clarity.", "pull request": "4010"}
{"Version": "v4.8.0", "section": "Docs", "text": "Various doc updates for library modules or user guides.", "pull request": "3615"}
{"Version": "v4.8.0", "section": "Docs", "text": "Additional clarifications or expansions in doc comments.", "pull request": "3664"}
{"Version": "v4.8.0", "section": "Docs", "text": "Edits to doc pages for clarity or completeness.", "pull request": "3707"}
{"Version": "v4.8.0", "section": "Docs", "text": "Refines docstrings or user-facing doc references in the codebase.", "pull request": "3734"}
{"Version": "v4.8.0", "section": "Docs", "text": "Minor doc improvements or reorganizations of existing references.", "pull request": "3868"}
{"Version": "v4.8.0", "section": "Docs", "text": "Edits or extends documentation for advanced features or modules.", "pull request": "3861"}
{"Version": "v4.8.0", "section": "Docs", "text": "Fixes or updates certain doc references in Lean code.", "pull request": "3869"}
{"Version": "v4.8.0", "section": "Docs", "text": "Further doc updates for specialized areas or linter references.", "pull request": "3858"}
{"Version": "v4.8.0", "section": "Docs", "text": "Expands doc coverage in some lesser-known library parts.", "pull request": "3856"}
{"Version": "v4.8.0", "section": "Docs", "text": "Syncs doc changes for tactics or macros with the code updates.", "pull request": "3857"}
{"Version": "v4.8.0", "section": "Docs", "text": "Updates docs to reflect changed or deprecated features in Lean 4.", "pull request": "3867"}
{"Version": "v4.8.0", "section": "Docs", "text": "Revises doc references in sections related to config or options.", "pull request": "3864"}
{"Version": "v4.8.0", "section": "Docs", "text": "Cleanups in doc references for library usage or style.", "pull request": "3860"}
{"Version": "v4.8.0", "section": "Docs", "text": "Minor enhancements for code examples in doc strings.", "pull request": "3859"}
{"Version": "v4.8.0", "section": "Docs", "text": "Doc improvements for certain library modules or theorems.", "pull request": "3871"}
{"Version": "v4.8.0", "section": "Docs", "text": "Expands user documentation and references for advanced usage.", "pull request": "3919"}
{"Version": "v4.8.0", "section": "Lean internals (Defeq and WHNF)", "text": "Adds better support for reducing Nat.rec expressions.", "pull request": "3616"}
{"Version": "v4.8.0", "section": "Lean internals (Defeq and WHNF)", "text": "Adds tracing for non-easy WHNF cases.", "pull request": "3774"}
{"Version": "v4.8.0", "section": "Lean internals (Defeq and WHNF)", "text": "Fixes isDefEq performance by trying structure eta after lazy delta.", "pull request": "3807"}
{"Version": "v4.8.0", "section": "Lean internals (Defeq and WHNF)", "text": "Prevents transparency level bump when reducing projections (yesWithDeltaI fix).", "pull request": "3816"}
{"Version": "v4.8.0", "section": "Lean internals (Defeq and WHNF)", "text": "Improves heuristics in isDefEq for certain matching scenarios.", "pull request": "3837"}
{"Version": "v4.8.0", "section": "Lean internals (Defeq and WHNF)", "text": "Enhances isDefEq to handle constraints like t.i =?= s.i more efficiently.", "pull request": "3965"}
{"Version": "v4.8.0", "section": "Lean internals (Defeq and WHNF)", "text": "Improves isDefEqProj logic for projections.", "pull request": "3977"}
{"Version": "v4.8.0", "section": "Lean internals (Defeq and WHNF)", "text": "Adds universe constraint approximations (u=?=max u ?v => ?v = u).", "pull request": "3981"}
{"Version": "v4.8.0", "section": "Lean internals (Defeq and WHNF)", "text": "Improves isDefEqProj in typeclass resolution contexts.", "pull request": "4004"}
{"Version": "v4.8.0", "section": "Lean internals (Defeq and WHNF)", "text": "Adds backward.isDefEq.lazyProjDelta and lazyWhnfCore for compat.", "pull request": "4012"}
{"Version": "v4.8.0", "section": "Lean internals (Kernel)", "text": "Removes dead code in the kernel.", "pull request": "3966"}
{"Version": "v4.8.0", "section": "Lean internals (Kernel)", "text": "Fixes mismatch for TheoremVal between Lean and C++ implementations.", "pull request": "4035"}
{"Version": "v4.8.0", "section": "Lean internals (Typeclass instance synthesis)", "text": "Eta-reduces synthesized instances to avoid unnecessary lambdas.", "pull request": "3638"}
{"Version": "v4.8.0", "section": "Lean internals (Typeclass instance synthesis)", "text": "Adds backward.synthInstance.canonInstances and restricts subgoals lacking metavars.", "pull request": "4008"}
{"Version": "v4.8.0", "section": "Lean internals (Definition processing)", "text": "Renames automatically generated equational theorems to .eq_<idx> instead of ._eq_<idx>.", "pull request": "3661"}
{"Version": "v4.8.0", "section": "Lean internals (Definition processing)", "text": "Refines equational theorem naming from ._unfold to .eq_def.", "pull request": "3767"}
{"Version": "v4.8.0", "section": "Lean internals (Definition processing)", "text": "Adds a mechanism to reserve names for certain definitions or theorems.", "pull request": "3675"}
{"Version": "v4.8.0", "section": "Lean internals (Definition processing)", "text": "Fixes name resolution for reserved names in namespaces and matchers.", "pull request": "3803"}
{"Version": "v4.8.0", "section": "Lean internals (Definition processing)", "text": "Treats nested non-proof definitions inside theorems as def instead of theorem.", "pull request": "3662"}
{"Version": "v4.8.0", "section": "Lean internals (Definition processing)", "text": "Makes proposition fields of structures automatically theorems.", "pull request": "4006"}
{"Version": "v4.8.0", "section": "Lean internals (Definition processing)", "text": "Issues an error if a theorem is marked extern.", "pull request": "4018"}
{"Version": "v4.8.0", "section": "Lean internals (Definition processing)", "text": "Improves performance for well-founded recursive definition equation generation.", "pull request": "4047"}
{"Version": "v4.8.0", "section": "Lean internals (Refactors)", "text": "Avoids unfolding in Lean.Meta.evalNat for simpler evaluation steps.", "pull request": "3614"}
{"Version": "v4.8.0", "section": "Lean internals (Refactors)", "text": "Centralizes Fix/GuessLex/FunInd logic in ArgsPacker module.", "pull request": "3621"}
{"Version": "v4.8.0", "section": "Lean internals (Refactors)", "text": "Rewrites the UnusedVariable linter for better performance.", "pull request": "3186"}
{"Version": "v4.8.0", "section": "Lean internals (Refactors)", "text": "Removes the coercion from String to Name, requiring manual mkSimple.", "pull request": "3589"}
{"Version": "v4.8.0", "section": "Lean internals (Refactors)", "text": "Removes lines field from FileMap, simplifying file mapping logic.", "pull request": "3237"}
{"Version": "v4.8.0", "section": "Lean internals (Refactors)", "text": "Makes the msg parameter to throwTacticEx optional for convenience.", "pull request": "3951"}
{"Version": "v4.8.0", "section": "Lean internals (Diagnostics)", "text": "Adds set_option diagnostics true to track unfolded declarations, etc.", "pull request": "4016"}
{"Version": "v4.8.0", "section": "Lean internals (Diagnostics)", "text": "Adds counters for used instances, reducible decls, isDefEq heuristics in diagnostics.", "pull request": "4019"}
{"Version": "v4.8.0", "section": "Lean internals (Diagnostics)", "text": "Expands diagnostic counters to recursor reductions and more details.", "pull request": "4020"}
{"Version": "v4.8.0", "section": "Lean internals (Diagnostics)", "text": "Displays exceptional hints for deterministic timeout with diagnostics true.", "pull request": "4030"}
{"Version": "v4.8.0", "section": "Lean internals (Diagnostics)", "text": "Shows max recursion info in diagnostics at certain failing points.", "pull request": "4031"}
{"Version": "v4.8.0", "section": "Lean internals (Diagnostics)", "text": "Adds set_option diagnostics for congruence theorem generation stats.", "pull request": "4049"}
{"Version": "v4.8.0", "section": "Lean internals (Other features)", "text": "Adds environment extension marking which defs use structural or well-founded recursion.", "pull request": "3800"}
{"Version": "v4.8.0", "section": "Lean internals (Other features)", "text": "Allows trace.profiler output to be exported to Firefox Profiler format.", "pull request": "3801"}
{"Version": "v4.8.0", "section": "Lean internals (Other features)", "text": "Introduces @[builtin_doc] attribute to store docs/location as builtin metadata.", "pull request": "3918"}
{"Version": "v4.8.0", "section": "Lean internals (Other features)", "text": "Extends builtin_doc usage or storage to more declarations.", "pull request": "3953"}
{"Version": "v4.8.0", "section": "Lean internals (Other features)", "text": "Adds lean --json CLI to print messages as JSON for external tooling.", "pull request": "3939"}
{"Version": "v4.8.0", "section": "Lean internals (Other features)", "text": "Improves test_extern command for verifying external definitions.", "pull request": "3075"}
{"Version": "v4.8.0", "section": "Lean internals (Other features)", "text": "Provides a monadic generalization of FindExpr, rewriting prior approach.", "pull request": "3970"}
{"Version": "v4.8.0", "section": "Lean internals (Docs)", "text": "Additional documentation clarifying internal Lean modules or flows.", "pull request": "3743"}
{"Version": "v4.8.0", "section": "Lean internals (Docs)", "text": "Expands doc references for elaboration or kernel internals.", "pull request": "3921"}
{"Version": "v4.8.0", "section": "Lean internals (Docs)", "text": "Documents new or refactored internal definitions in the Lean codebase.", "pull request": "3954"}
{"Version": "v4.8.0", "section": "Lean internals (Other fixes)", "text": "Addresses certain edge cases in internal elaboration (#3622).", "pull request": "3622"}
{"Version": "v4.8.0", "section": "Lean internals (Other fixes)", "text": "Fixes issues with a parse or macro usage (#3726).", "pull request": "3726"}
{"Version": "v4.8.0", "section": "Lean internals (Other fixes)", "text": "Resolves partial flaws in auto-bound implicits (#3823).", "pull request": "3823"}
{"Version": "v4.8.0", "section": "Lean internals (Other fixes)", "text": "Improves logic in certain kernel or meta checks (#3897).", "pull request": "3897"}
{"Version": "v4.8.0", "section": "Lean internals (Other fixes)", "text": "Corrects a bug in isDefEq or transparency usage (#3964).", "pull request": "3964"}
{"Version": "v4.8.0", "section": "Lean internals (Other fixes)", "text": "Fixes mismatch in environment handling (#3946).", "pull request": "3946"}
{"Version": "v4.8.0", "section": "Lean internals (Other fixes)", "text": "Resolves an issue in a certain elaboration step (#4007).", "pull request": "4007"}
{"Version": "v4.8.0", "section": "Lean internals (Other fixes)", "text": "Adjusts or cleans up code for tactic usage (#4026).", "pull request": "4026"}
{"Version": "v4.8.0", "section": "Compiler, runtime, and FFI", "text": "Allocates/frees thread-local runtime resources for threads not started by Lean.", "pull request": "3632"}
{"Version": "v4.8.0", "section": "Compiler, runtime, and FFI", "text": "Improves error message about compacting closures for clarity.", "pull request": "3627"}
{"Version": "v4.8.0", "section": "Compiler, runtime, and FFI", "text": "Fixes a deadlock in IO.Promise.resolve calls.", "pull request": "3692"}
{"Version": "v4.8.0", "section": "Compiler, runtime, and FFI", "text": "Catches MoveFileEx errors on Windows for better diagnostics.", "pull request": "3753"}
{"Version": "v4.8.0", "section": "Compiler, runtime, and FFI", "text": "Fixes double reset bug in ResetReuse transformation for memory reuse.", "pull request": "4028"}
{"Version": "v4.8.0", "section": "Lake (TOML configuration)", "text": "Adds support for lakefile.toml as alternative to lakefile.lean with partial feature set.", "pull request": "3298"}
{"Version": "v4.8.0", "section": "Lake (TOML configuration)", "text": "Introduces lake translate-config for migrating .lean to .toml or vice versa.", "pull request": "4104"}
{"Version": "v4.8.0", "section": "Lake (Build progress overhaul)", "text": "Overhauls build flow with a top-level Lake build monitor for standardized logs.", "pull request": "3835"}
{"Version": "v4.8.0", "section": "Lake (Build progress overhaul)", "text": "Improves job isolation so stray I/O or import errors don't abort entire build.", "pull request": "4115"}
{"Version": "v4.8.0", "section": "Lake (Build progress overhaul)", "text": "Adds color and in-place progress lines with --ansi or --no-ansi.", "pull request": "4127"}
{"Version": "v4.8.0", "section": "Lake (Build progress overhaul)", "text": "Implements --wfail and --iofail to fail on warnings or log messages.", "pull request": "4220"}
{"Version": "v4.8.0", "section": "Lake (Build progress overhaul)", "text": "Refines build job output formatting for consistent progress reporting.", "pull request": "4232"}
{"Version": "v4.8.0", "section": "Lake (Build progress overhaul)", "text": "Localizes module import errors to their respective build jobs.", "pull request": "4236"}
{"Version": "v4.8.0", "section": "Lake (lake test)", "text": "Adds a built-in lake test command to run a test_runner-labeled script/exe.", "pull request": "3779"}
{"Version": "v4.8.0", "section": "Lake (lake lean)", "text": "New command lake lean <file> builds the imports before running lean on it.", "pull request": "3793"}
{"Version": "v4.8.0", "section": "Lake (Other fixes)", "text": "Adds LEAN_GITHASH env var to override Git hash used in trace computation.", "pull request": "3609"}
{"Version": "v4.8.0", "section": "Lake (Other fixes)", "text": "Improves relative package directory path normalization in pre-rename checks.", "pull request": "3795"}
{"Version": "v4.8.0", "section": "Lake (Other fixes)", "text": "Fixes handling of packages repeated in a dependency tree.", "pull request": "3957"}
{"Version": "v4.8.0", "section": "Lake (Other fixes)", "text": "Makes it an error if package name mismatches the require name, warns about std->batteries rename.", "pull request": "3999"}
{"Version": "v4.8.0", "section": "Lake (Other fixes)", "text": "Fixes quiet mode so it suppresses build output properly.", "pull request": "4033"}
{"Version": "v4.8.0", "section": "Lake (Docs)", "text": "Adds or updates Lake documentation for usage and advanced config options.", "pull request": "3704"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Adds a release process checklist for maintainers to follow.", "pull request": "3536"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Extends the release checklist or merges improvements to it.", "pull request": "3833"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Runs nix-ci more uniformly across different build/test steps.", "pull request": "3600"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Avoids argument limit issues on Windows builds by adjusting build scripts.", "pull request": "3612"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Builds Lean's .o files in parallel with other core components.", "pull request": "3682"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Changes how Lean is built on Windows, requiring dynamic linking for supportInterpreter.", "pull request": "3601"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Marks 'Build matrix complete' as canceled if the entire build is canceled.", "pull request": "3690"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Fixes or updates CI steps for certain steps like #3700 usage.", "pull request": "3700"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Refines workflow steps to handle #3702 improvements in CI scripts.", "pull request": "3702"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Additional fix or improvement in #3701 for std/mathlib CI integration.", "pull request": "3701"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Tweaks or merges #3834 improvements for standard library CI.", "pull request": "3834"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Applies #3923 changes for mathlib CI or general project CI improvements.", "pull request": "3923"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Fixes nix build . on macOS (#3712).", "pull request": "3712"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Replaces shell.nix with flake.nix in devShell (#3717).", "pull request": "3717"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Adds test result summaries after certain runs (#3715).", "pull request": "3715"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Prevents stage0 changes from merging without proper checks (#3971).", "pull request": "3971"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Adds handling for changes-stage0 label in the merge queue (#3979).", "pull request": "3979"}
{"Version": "v4.8.0", "section": "DevOps", "text": "Adds a script to summarize GitHub issues (#3952).", "pull request": "3952"}
{"Version": "v4.8.0", "section": "Breaking changes", "text": "Large Lake build refactor changes output format and certain Lake APIs.", "pull request": "3601"}
{"Version": "v4.8.0", "section": "Breaking changes", "text": "Executables with supportInterpreter on Windows must run via lake exe to find DLLs.", "pull request": "3601"}
{"Version": "v4.8.0", "section": "Breaking changes", "text": "Equational theorems renamed from ._eq_<idx> to .eq_<idx>, and ._unfold to .eq_def.", "pull request": "3661"}
{"Version": "v4.7.0", "section": "Language features", "text": "Simp and rw skip instance resynthesis by default; revert with `set_option tactic.skipAssignedInstances false`.", "pull request": "3507"}
{"Version": "v4.7.0", "section": "Language features", "text": "Simp and rw skip instance resynthesis by default; revert with `set_option tactic.skipAssignedInstances false`.", "pull request": "3509"}
{"Version": "v4.7.0", "section": "Pretty printing", "text": "When `pp.proofs = false`, omitted proofs now display as `⋯` instead of `_`.", "pull request": "3241"}
{"Version": "v4.7.0", "section": "Pretty printing", "text": "pp.proofs.withType is now false by default.", "pull request": "none"}
{"Version": "v4.7.0", "section": "Pretty printing", "text": "App delaborator handles over-application so extra-arg cases in app_unexpanders are unnecessary.", "pull request": "3495"}
{"Version": "v4.7.0", "section": "Simp/dsimp config", "text": "Adds `zetaDelta` option (false by default); see #2682 for details on zeta vs zetaDelta.", "pull request": "2682"}
{"Version": "v4.7.0", "section": "Simp local theorems", "text": "Local theorems for simp assume function arguments are `no_index`, restoring Lean 3 behavior.", "pull request": "2670"}
{"Version": "v4.7.0", "section": "Tactics", "text": "Improved error messages for `decide` tactic.", "pull request": "3422"}
{"Version": "v4.7.0", "section": "IDE/Performance", "text": "Improved auto-completion performance.", "pull request": "3460"}
{"Version": "v4.7.0", "section": "IDE/Performance", "text": "Faster initial language server startup.", "pull request": "3552"}
{"Version": "v4.7.0", "section": "IDE/Call hierarchy", "text": "Sort entries and remove private header from displayed names in call hierarchy.", "pull request": "3482"}
{"Version": "v4.7.0", "section": "Parsing", "text": "Added a low-level error recovery combinator for DSLs.", "pull request": "3413"}
{"Version": "v4.7.0", "section": "Termination inference", "text": "`termination_by?` reveals inferred argument and can convert to `termination_by` via code action.", "pull request": "3514"}
{"Version": "v4.7.0", "section": "Arithmetic ops", "text": "`/` and `%` on `Int` now use `Int.ediv` and `Int.emod`, with kernel support. (Change for non-Std users.)", "pull request": "3376"}
{"Version": "v4.7.0", "section": "omega tactic", "text": "Now in core; supplemented by `bv_omega` for BitVec linear arithmetic.", "pull request": "3435"}
{"Version": "v4.7.0", "section": "omega tactic", "text": "Supports `Fin` type.", "pull request": "3427"}
{"Version": "v4.7.0", "section": "omega tactic", "text": "Supports `<<<` operator.", "pull request": "3433"}
{"Version": "v4.7.0", "section": "omega tactic", "text": "No longer identifies atoms up to definitional equality; can't prove `id x ≤ x` automatically.", "pull request": "3525"}
{"Version": "v4.7.0", "section": "omega tactic", "text": "Used in Lean's automation for termination proofs.", "pull request": "3503"}
{"Version": "v4.7.0", "section": "omega tactic", "text": "Used in array indexing proofs.", "pull request": "3515"}
{"Version": "v4.7.0", "section": "Library search tactics", "text": "`exact?`/`apply?`/`solve_by_elim` from Std are now in core Lean.", "pull request": "none"}
{"Version": "v4.7.0", "section": "Tactic commands", "text": "New `#check_tactic` and `#check_simp` for verifying tactic behavior.", "pull request": "none"}
{"Version": "v4.7.0", "section": "App unexpanders", "text": "Delaborator tries unexpanders on every prefix, registering TermInfo properly for subexpressions.", "pull request": "3375"}
{"Version": "v4.7.0", "section": "Breaking changes", "text": "Stronger `MonadAlwaysExcept` requirement for `Lean.withTraceNode` and variants.", "pull request": "none"}
{"Version": "v4.7.0", "section": "Breaking changes", "text": "`match ... with.` replaced by `nomatch` syntax from Std.", "pull request": "3279"}
{"Version": "v4.7.0", "section": "Breaking changes", "text": "`fun.` replaced by `nofun` syntax from Std.", "pull request": "3286"}
{"Version": "v4.7.0", "section": "simp bugfixes", "text": "Avoid crash when `simp` loops indefinitely.", "pull request": "3269"}
{"Version": "v4.7.0", "section": "simp bugfixes", "text": "`simp` no longer gets stuck on autoParam premises.", "pull request": "3315"}
{"Version": "v4.7.0", "section": "simp bugfixes", "text": "`simp` doesn't fail when a custom discharger makes no progress.", "pull request": "3317"}
{"Version": "v4.7.0", "section": "simp bugfixes", "text": "`simp` can now discharge autoParam premises reduced to True.", "pull request": "3314"}
{"Version": "v4.7.0", "section": "simp bugfixes", "text": "`simp?` suggests generated equation lemma names (part 1).", "pull request": "3547"}
{"Version": "v4.7.0", "section": "simp bugfixes", "text": "`simp?` suggests generated equation lemma names (part 2).", "pull request": "3573"}
{"Version": "v4.7.0", "section": "match expressions", "text": "Fix regression with builtin literals in match.", "pull request": "3521"}
{"Version": "v4.7.0", "section": "match expressions", "text": "Accept match over BitVec finite types.", "pull request": "3538"}
{"Version": "v4.7.0", "section": "match expressions", "text": "Fix matching on Int literals.", "pull request": "3504"}
{"Version": "v4.7.0", "section": "match expressions", "text": "Allow patterns containing int values/constructors in match.", "pull request": "3496"}
{"Version": "v4.7.0", "section": "termination_by", "text": "Improved error messages for `termination_by` usage.", "pull request": "3255"}
{"Version": "v4.7.0", "section": "rename_i fix", "text": "Fix rename_i in macros (part 1).", "pull request": "3553"}
{"Version": "v4.7.0", "section": "rename_i fix", "text": "Fix rename_i in macros (part 2).", "pull request": "3581"}
{"Version": "v4.7.0", "section": "generalize tactic", "text": "Fix excessive resource usage in `generalize` (part 1).", "pull request": "3524"}
{"Version": "v4.7.0", "section": "generalize tactic", "text": "Fix excessive resource usage in `generalize` (part 2).", "pull request": "3575"}
{"Version": "v4.7.0", "section": "equation lemma", "text": "AutoParam arguments fail to rewrite (part 1).", "pull request": "2243"}
{"Version": "v4.7.0", "section": "equation lemma", "text": "AutoParam arguments fail to rewrite (part 2).", "pull request": "3316"}
{"Version": "v4.7.0", "section": "add_decl_doc", "text": "`add_decl_doc` now checks that declarations are local.", "pull request": "3311"}
{"Version": "v4.7.0", "section": "inductives fix", "text": "Instantiate types of inductives with correct parameters (part 1).", "pull request": "3242"}
{"Version": "v4.7.0", "section": "inductives fix", "text": "Instantiate types of inductives with correct parameters (part 2).", "pull request": "3246"}
{"Version": "v4.7.0", "section": "simprocs", "text": "New simprocs for many basic types.", "pull request": "3407"}
{"Version": "v4.7.0", "section": "Lake fixes", "text": "Warn on cloud release fetch failures.", "pull request": "3401"}
{"Version": "v4.7.0", "section": "Lake fixes", "text": "Handle trace & `lake build :release` errors better.", "pull request": "3248"}
{"Version": "v4.6.1", "section": "Performance", "text": "Backport of #3552 fixing a performance regression in server startup.", "pull request": "3552"}
{"Version": "v4.6.0", "section": "Simp", "text": "Added custom simplification procedures (simprocs) to `simp`, controllable via `set_option simprocs false` or by specifying them in `simp` commands.", "pull request": "none"}
{"Version": "v4.6.0", "section": "Termination hints", "text": "Overhauled `termination_by` and `decreasing_by` syntax and placement, removing function names and placing them next to their respective definitions.", "pull request": "none"}
{"Version": "v4.6.0", "section": "Termination hints", "text": "Changed semantics of `decreasing_by` so the tactic is applied to all termination proof goals together.", "pull request": "none"}
{"Version": "v4.6.0", "section": "InfoTree.context", "text": "Modified to allow partial contexts during command elaboration, breaking some manual InfoTree traversals.", "pull request": "3159"}
{"Version": "v4.6.0", "section": "Language server", "text": "Added call hierarchy support; requires a full rebuild for new .ilean format.", "pull request": "3082"}
{"Version": "v4.6.0", "section": "Structure instances", "text": "Multiple sources are filled strictly left-to-right, avoiding unnecessary eta expansion and reducing CPU usage.", "pull request": "2478"}
{"Version": "v4.6.0", "section": "Structure instances", "text": "RFC discussion for the new structure instance elaborator approach.", "pull request": "2451"}
{"Version": "v4.6.0", "section": "Pretty printing", "text": "Added `pp.deepTerms` and `pp.deepTerms.threshold` to omit printing deeply nested terms.", "pull request": "3201"}
{"Version": "v4.6.0", "section": "Pretty printing", "text": "Added `pp.numeralTypes` and `pp.natLit` options to show type ascriptions on number literals or print them as `nat_lit`.", "pull request": "2933"}
{"Version": "v4.6.0", "section": "Pretty printing", "text": "Further discussion about numeral printing conventions.", "pull request": "3021"}
{"Version": "v4.6.0", "section": "Lake", "text": "Improved platform information and control.", "pull request": "3226"}
{"Version": "v4.6.0", "section": "Lake", "text": "Allowed `lake update` from unsupported manifest versions.", "pull request": "3149"}
{"Version": "v4.6.0", "section": "Other improvements", "text": "`intro` now aware of `let_fun`.", "pull request": "3115"}
{"Version": "v4.6.0", "section": "Other improvements", "text": "Produce simpler proof terms in `rw` tactic.", "pull request": "3121"}
{"Version": "v4.6.0", "section": "Other improvements", "text": "Fuse nested `mkCongrArg` calls in `simp` proofs.", "pull request": "3203"}
{"Version": "v4.6.0", "section": "Other improvements", "text": "`induction using` now supports a general term.", "pull request": "3188"}
{"Version": "v4.6.0", "section": "Other improvements", "text": "Allow generalization in `let`; fixes #3065.", "pull request": "3060"}
{"Version": "v4.6.0", "section": "Other improvements", "text": "Out-of-bounds `swap!` returns `a`, not `default`; fixes #3196.", "pull request": "3197"}
{"Version": "v4.6.0", "section": "Other improvements", "text": "Derive `BEq` on structures with `Prop` fields; fixes #3140.", "pull request": "3191"}
{"Version": "v4.6.0", "section": "Other improvements", "text": "Refine through more `casesOnApp`/`matcherApp`; fixes #3175.", "pull request": "3176"}
{"Version": "v4.6.0", "section": "Other improvements", "text": "Do not strip dotted components from module names; fixes #2999.", "pull request": "2994"}
{"Version": "v4.6.0", "section": "Other improvements", "text": "Fix `deriving` only applying to the first declaration; fixes #3057.", "pull request": "3058"}
{"Version": "v4.6.0", "section": "Other improvements", "text": "Prevent metavariable instantiation for disallowed occurrences in kabstract/rw; fixes #2538.", "pull request": "2539"}
{"Version": "v4.6.0", "section": "Other improvements", "text": "Hover info for `cases h : ...` constructs.", "pull request": "3084"}
{"Version": "v4.5.0", "section": "String syntax", "text": "Modify lexical syntax of string literals to have string gaps, allowing multi-line strings without extra whitespace.", "pull request": "2821"}
{"Version": "v4.5.0", "section": "String syntax", "text": "Discussion of string-gap design and motivation in RFC #2838.", "pull request": "2838"}
{"Version": "v4.5.0", "section": "String syntax", "text": "Add raw string literal syntax: `r\"...\"` with optional `#` for quoting double quotes inside.", "pull request": "2929"}
{"Version": "v4.5.0", "section": "String syntax", "text": "Issue tracking raw string literal request and design details.", "pull request": "1422"}
{"Version": "v4.5.0", "section": "Termination", "text": "Removed `termination_by'`; use `termination_by` or `WellFounded.wrap` as alternatives.", "pull request": "none"}
{"Version": "v4.5.0", "section": "LSP", "text": "Support snippet edits in `TextEdit`s (see `Lean.Lsp.SnippetString`) for advanced code actions.", "pull request": "none"}
{"Version": "v4.5.0", "section": "Widget API", "text": "UserWidgetDefinition→Widget.Module; see `@[widget_module]`. Also adds `show_panel_widgets` and `RpcEncodable` props in infotree.", "pull request": "2963"}
{"Version": "v4.5.0", "section": "Termination inference", "text": "If no lexicographic measure is found, an explanation is given to help with debugging.", "pull request": "2960"}
{"Version": "v4.5.0", "section": "Termination inference", "text": "`set_option showInferredTerminationBy true` prints auto-generated `termination_by` clauses.", "pull request": "3012"}
{"Version": "v4.5.0", "section": "Mutual blocks", "text": "More detailed errors for invalid mutual recursion blocks.", "pull request": "2949"}
{"Version": "v4.5.0", "section": "simp?", "text": "Improvements to the output of `simp?` and `simp_all?` (first set).", "pull request": "2923"}
{"Version": "v4.5.0", "section": "simp?", "text": "Further improvements to `simp?` and `simp_all?` (second set).", "pull request": "2969"}
{"Version": "v4.5.0", "section": "Tactics", "text": "Tactics using `withLocation *` no longer fail if they close the main goal.", "pull request": "2917"}
{"Version": "v4.5.0", "section": "Extern testing", "text": "New `test_extern` command for testing `@[extern]` or `@[implemented_by]` functions.", "pull request": "none"}
{"Version": "v4.5.0", "section": "Bug fixes", "text": "Fixes for issues #2853, #2953, #2966, #2971, #2990, #3094.", "pull request": "none"}
{"Version": "v4.5.0", "section": "Bug fixes", "text": "Fixed eager evaluation in `Option.getD` (#3043), prevented panic in `leanPosToLspPos` (#3071), improved short-circuit for `List.all/any` (#2972).", "pull request": "none"}
{"Version": "v4.5.0", "section": "Lake bug fixes", "text": "Addressed issues #3036, #3064, #3069 in Lake.", "pull request": "none"}
{"Version": "v4.4.0", "section": "Lake/server options", "text": "Per-package server options (`leanOptions`/`moreServerOptions`); `moreServerArgs`→`moreGlobalServerArgs` deprecated.", "pull request": "2858"}
{"Version": "v4.4.0", "section": "Language server", "text": "Implemented rename request handler (LSP).", "pull request": "2462"}
{"Version": "v4.4.0", "section": "Language server", "text": "Import auto-completion feature.", "pull request": "2904"}
{"Version": "v4.4.0", "section": "Pretty printing", "text": "Added `pp.beta` to apply beta reduction in pretty printing.", "pull request": "2864"}
{"Version": "v4.4.0", "section": "Compiler", "text": "Embed and check githash in .olean for build verification.", "pull request": "2766"}
{"Version": "v4.4.0", "section": "Termination inference", "text": "Guess lexicographic order for well-founded recursion automatically.", "pull request": "2874"}
{"Version": "v4.4.0", "section": "Syntax", "text": "Allow trailing commas in tuples, lists, and tactics.", "pull request": "2643"}
{"Version": "v4.4.0", "section": "Bug fixes", "text": "Fixes #2628, #2883, #2810, #2925, #2914 in core or server code.", "pull request": "none"}
{"Version": "v4.4.0", "section": "Lake", "text": "Update package creation: `lake init .` uses current dir name, disallows invalid pkg names, no uppercase conversion for `lean_lib`, supports non-ident libs, filters irrelevant env extensions, re-unpacks cloud releases, simpler math template, parse build targets in `lake exe`, shadowing for later packages, excludes exe roots from importable modules.", "pull request": "2890"}
{"Version": "v4.4.0", "section": "Lake", "text": "Disallow invalid package names (#2637).", "pull request": "2637"}
{"Version": "v4.4.0", "section": "Lake", "text": "No uppercase conversion for `lean_lib` (#2567).", "pull request": "2567"}
{"Version": "v4.4.0", "section": "Lake", "text": "Support non-identifier library names (#2865).", "pull request": "2865"}
{"Version": "v4.4.0", "section": "Lake", "text": "Filter irrelevant env extensions (#2632).", "pull request": "2632"}
{"Version": "v4.4.0", "section": "Lake", "text": "Re-unpack cloud releases if build dir is removed (#2928).", "pull request": "2928"}
{"Version": "v4.4.0", "section": "Lake", "text": "Simplified math template (#2930).", "pull request": "2930"}
{"Version": "v4.4.0", "section": "Lake", "text": "Parse build target in `lake exe` (#2932).", "pull request": "2932"}
{"Version": "v4.4.0", "section": "Lake", "text": "Shadow later packages over earlier ones (#2937).", "pull request": "2937"}
{"Version": "v4.3.0", "section": "Simp tactic", "text": "`simp [f]` no longer unfolds partial applications of `f` by default (#2042). Use `unfold f` or `simp (config := { unfoldPartialApp := true }) [f]`.", "pull request": "2042"}
{"Version": "v4.3.0", "section": "Simp tactic", "text": "Does not use `Decidable` rewriting unless `decide := true` is set in config. (`simp` won't close all decidable goals).", "pull request": "none"}
{"Version": "v4.3.0", "section": "Bug fixes", "text": "Addresses #2778, #2790, #2552, #1926, #2669, #2281, #2711, #2685, #2514, #2729, #2361, #2178. Also cancels tasks on doc edit (#2648), removes extra `%` from `Fin.mod` (#2688), avoids DecidableEq in `Array.mem` (#2774), unifies `USize.size` (#1926), better emacs eglot (#2721).", "pull request": "none"}
{"Version": "v4.3.0", "section": "Lake", "text": "Sensible defaults for `lake new MyProject math` (#2770), replaced `postUpdate?` with `post_update` (#185), auto-create manifest (#2680), deprecated `:=` syntax in config, `LAKE_PKG_URL_MAP` for overriding URLs (#2709), moved outputs to `.lake` (#2713), updated manifest to v7 (#2801), stricter `lakefile.olean` checks (#2842).", "pull request": "2770"}
{"Version": "v4.3.0", "section": "Lake", "text": "Replace `postUpdate?` with `post_update` (#185).", "pull request": "185"}
{"Version": "v4.3.0", "section": "Lake", "text": "Auto-create manifest if missing (#2680).", "pull request": "2680"}
{"Version": "v4.3.0", "section": "Lake", "text": "Override package URLs with `LAKE_PKG_URL_MAP` (#2709).", "pull request": "2709"}
{"Version": "v4.3.0", "section": "Lake", "text": "Move outputs to `.lake` (#2713).", "pull request": "2713"}
{"Version": "v4.3.0", "section": "Lake", "text": "Updated manifest format to version 7 (#2801).", "pull request": "2801"}
{"Version": "v4.3.0", "section": "Lake", "text": "Stricter checks on `lakefile.olean` (#2842).", "pull request": "2842"}
{"Version": "v4.2.0", "section": "isDefEq", "text": "Cache for terms not containing metavariables (#2644).", "pull request": "2644"}
{"Version": "v4.2.0", "section": "Kernel/Environment", "text": "Made `Environment.mk`/`Environment.add` private; safer `replay` method (#2604).", "pull request": "2604"}
{"Version": "v4.2.0", "section": "Kernel/Environment", "text": "Follow-up environment changes for add (#2642) and replay (#2617).", "pull request": "2642"}
{"Version": "v4.2.0", "section": "Kernel/Environment", "text": "Also reference #2617 (replay) for safe environment modifications.", "pull request": "2617"}
{"Version": "v4.2.0", "section": "IO.Process", "text": "`IO.Process.output` no longer inherits stdin of the caller.", "pull request": "none"}
{"Version": "v4.2.0", "section": "Performance", "text": "Do not inhibit caching of default-level match reduction (#2612).", "pull request": "2612"}
{"Version": "v4.2.0", "section": "Error messages", "text": "List valid case tags on invalid input (#2629).", "pull request": "2629"}
{"Version": "v4.2.0", "section": "Derive handlers", "text": "Support `DecidableEq` on mutual inductives (#2591).", "pull request": "2591"}
{"Version": "v4.2.0", "section": "Lake", "text": "Show path of failed import (#2616), fix macOS linker warnings (#2598), add `postUpdate?` config, improve startup (#2572, #2573).", "pull request": "2616"}
{"Version": "v4.2.0", "section": "Lake", "text": "Fix macOS linker warnings (#2598).", "pull request": "2598"}
{"Version": "v4.2.0", "section": "Lake", "text": "Improved startup time (#2572).", "pull request": "2572"}
{"Version": "v4.2.0", "section": "Lake", "text": "Further improvement to startup (#2573).", "pull request": "2573"}
{"Version": "v4.2.0", "section": "Tactics", "text": "`refine e` only yields newly-created metavars, preventing duplicated or closed goals (#2502).", "pull request": "2502"}
{"Version": "v4.1.0", "section": "Error messages", "text": "Improve positioning on missing tokens in incomplete tactic proofs (#2393).", "pull request": "2393"}
{"Version": "v4.1.0", "section": "Lake OLean cache", "text": "Lake caches `lakefile.lean` in `lakefile.olean`; use `-R/--reconfigure` if config changed.", "pull request": "none"}
{"Version": "v4.1.0", "section": "Lake buildO", "text": "Signature changed: args→weakArgs/traceArgs separation.", "pull request": "none"}
{"Version": "v4.1.0", "section": "Imports", "text": "Use `Array Import` in `importModules`, `headerToImports`, `parseImports` (#2480).", "pull request": "2480"}
{"Version": "v4.1.0", "section": "Rewrite config", "text": "`occs` field in `Rewrite.Config` for controlling pattern occurrences (#2470).", "pull request": "2470"}
{"Version": "v4.0.0", "section": "Meta API", "text": "Renamed `Lean.Meta.getConst?` to `getUnfoldableConst?` and `getConstNoEx?` to `getUnfoldableConstNoEx?`. Use `Lean.getConstInfo` instead for public API.", "pull request": "2454"}
{"Version": "v4.0.0", "section": "simp/dsimp", "text": "`dsimp / simp / simp_all` now fail by default if they make no progress. Use `(config := { failIfUnchanged := false })` to override.", "pull request": "2336"}
{"Version": "v4.0.0", "section": "simp_all", "text": "`simp_all` now preserves hypothesis order more consistently. This may affect tactics that rely on ordering (rename_i, case, next).", "pull request": "2334"}
{"Version": "v4.0.0", "section": "have this", "text": "`this` is now a regular identifier introduced by `have :=` in the current tactic block. Previously it was a keyword visible in all scopes.", "pull request": "2247"}
{"Version": "v4.0.0", "section": "Profiling", "text": "Show typeclass and tactic names in profiler output.", "pull request": "2170"}
{"Version": "v4.0.0", "section": "calc indentation", "text": "`calc` requires consistent indentation for relation/proof pairs. Also supports underscores `_` in the first relation.", "pull request": "1844"}
{"Version": "v4.0.0", "section": "Lake", "text": "Update Lake to latest prerelease version.", "pull request": "none"}
{"Version": "v4.0.0", "section": "IDE/LS", "text": "Go-to-definition on typeclass projection applications goes to the instance(s).", "pull request": "1767"}
{"Version": "v4.0.0", "section": "Profiling", "text": "Include timings in trace messages when `profiler = true`.", "pull request": "1995"}
{"Version": "v4.0.0", "section": "Hover/#check", "text": "Pretty-print signatures in hover and `#check <ident>` results.", "pull request": "1943"}
{"Version": "v4.0.0", "section": "Parser", "text": "Introduce parser memoization to avoid exponential behavior in ambiguous grammars.", "pull request": "1799"}
{"Version": "v4.0.0", "section": "Syntax expansions", "text": "Allow `doSeq` in `let x <- e | seq` pattern (partial/do-block scenario).", "pull request": "1809"}
{"Version": "v4.0.0", "section": "IDE/LS", "text": "Hover/go-to-def/refs for options (e.g. set_option).", "pull request": "1783"}
{"Version": "v4.0.0", "section": "Syntax", "text": "Add empty type ascription `(e :)` to indicate expression type is not yet known.", "pull request": "1797"}
{"Version": "v4.0.0", "section": "Parser", "text": "Make tokens in `<|>` relevant to syntax match (fix parse ambiguities).", "pull request": "1744"}
{"Version": "v4.0.0", "section": "Linter", "text": "Add `linter.deprecated` option to silence deprecation warnings.", "pull request": "1768"}
{"Version": "v4.0.0", "section": "Auto-completion", "text": "Improve fuzzy-matching heuristics for completions.", "pull request": "1710"}
{"Version": "v4.0.0", "section": "Implementation-detail hypotheses", "text": "Support hidden/implementation-only hypotheses that appear in tactic proofs for internal usage.", "pull request": "1692"}
{"Version": "v4.0.0", "section": "cases/induction", "text": "Hover info for `cases` or `induction` case names, referencing pattern variables.", "pull request": "1660"}
{"Version": "v4.0.0", "section": "Parser", "text": "Prefer longer parse branch even if unsuccessful, for better error messages in ambiguous contexts.", "pull request": "1658"}
{"Version": "v4.0.0", "section": "Hover info", "text": "Show the declaration module name in hover text.", "pull request": "1638"}
{"Version": "v4.0.0", "section": "conv mode", "text": "New `conv` structuring tactics for advanced rewriting.", "pull request": "1636"}
{"Version": "v4.0.0", "section": "simp trace", "text": "`simp` can track steps and print an equivalent `simp only` set. Useful for debugging. (Simp steps recorded.)", "pull request": "1626"}
{"Version": "v4.0.0", "section": "Indentation", "text": "Uniform indentation required in tactic blocks/do blocks. (Issue #1606 references.)", "pull request": "none"}
{"Version": "v4.0.0", "section": "AssocList/HashMap/RBMap", "text": "Moved these data structures into Lean package. Standard library (std4) will evolve them independently.", "pull request": "none"}
{"Version": "v4.0.0", "section": "std4 library", "text": "Std library moved to separate std4 repository on GitHub.", "pull request": "none"}
{"Version": "v4.0.0", "section": "InteractiveGoals", "text": "`InteractiveGoals` now includes info about changed parts of a goal after applying a tactic.", "pull request": "1610"}
{"Version": "v4.0.0", "section": "Docstrings", "text": "Add `[inheritDoc]` attribute for reusing docstrings across declarations.", "pull request": "1480"}
{"Version": "v4.0.0", "section": "panic behavior", "text": "Expose that `panic = default` in more contexts (lower-level improvements).", "pull request": "1614"}
{"Version": "v4.0.0", "section": "LCNF codegen", "text": "New code generator project in `src/Lean/Compiler/LCNF` has started.", "pull request": "none"}
{"Version": "v4.0.0", "section": "register_simp_attr", "text": "Remove optional description parameter from `register_simp_attr` command.", "pull request": "1566"}
{"Version": "v4.0.0", "section": "Concurrency", "text": "Additional concurrency primitives (futures, channels, etc.).", "pull request": "1555"}
{"Version": "v4.0.0", "section": "Traces", "text": "Support collapsible traces with messages for improved debugging views.", "pull request": "1448"}
{"Version": "v4.0.0", "section": "Namespaces", "text": "Hygienic resolution of namespaces in macros and expansions.", "pull request": "1442"}
{"Version": "v4.0.0", "section": "Float", "text": "New `Float` functions for arithmetic or conversions.", "pull request": "1460"}
{"Version": "v4.0.0", "section": "Init docstrings", "text": "Added many new docstrings to declarations in `Init`.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Lake", "text": "Update Lake to v4.0.0. See Lake's v4.0.0 release notes for changes.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Mutual declarations", "text": "Support mutual declarations in different namespaces. The compiler auto-creates a common prefix namespace.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "deriving handlers", "text": "Allow user-defined deriving handlers for existing typeclasses. See `tests/pkg/deriving/UserDeriving` for example.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Tactics", "text": "Add `congr (num)?`. This tactic helps prove equality by structural decomposition of function arguments.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Lint", "text": "Missing doc linter for declarations lacking docstrings (#1390).", "pull request": "1390"}
{"Version": "v4.0.0-m5", "section": "match syntax", "text": "Check for unused alternatives in `match`. (#1371).", "pull request": "1371"}
{"Version": "v4.0.0-m5", "section": "Completion", "text": "Auto-completion for structure instance fields and dotted identifier notation (#123?).", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "nat_lit", "text": "No longer needed for `OfNat` instances. E.g., `instance : OfNat Bit 0` is valid.", "pull request": "1389"}
{"Version": "v4.0.0-m5", "section": "Attributes", "text": "Add `[elabAsElim]` to mimic Lean 3's `elab_as_eliminator` for custom induction usage.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Trans class", "text": "`Trans` now accepts relations in `Type u`, enabling more flexible rewriting in calc expressions.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Constructors", "text": "Allow unescaped keywords as inductive constructor names, using dot notation to avoid conflicts.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Local instance check", "text": "Error if parametric local instances are not forward-dependent, can disable via `set_option checkBinderAnnotations false`.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "pp.showLetValues", "text": "New option to hide let-binders' RHS in goals. Defaults to `true` in tactic-mode, `false` otherwise.", "pull request": "1345"}
{"Version": "v4.0.0-m5", "section": "warningAsError", "text": "Option `warningAsError` treats warnings as errors at elaboration time.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Patterns", "text": "Support dotted notation and named arguments in match/pattern syntax, e.g. `.forallE (binderType := type) .. => type`.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Attributes references", "text": "Go-to-definition for references in attributes like `@[implementedBy func]`, `@[tactic parserName]`, etc.", "pull request": "1350"}
{"Version": "v4.0.0-m5", "section": "MVarId discoverability", "text": "Add easier-to-find MVarId methods, deprecate older ones. (#1346 references further improvements).", "pull request": "1346"}
{"Version": "v4.0.0-m5", "section": "deprecated attribute", "text": "Mark declarations with `[deprecated]`. Warnings suggest the recommended replacement if given.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "LevelMVarId", "text": "New type `LevelMVarId` (aka `LMVarId`) for universe metavars, preventing confusion with expr metavars.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "calc improvements", "text": "Improvements to the `calc` syntax and tactics (issue #1342 references).", "pull request": "1342"}
{"Version": "v4.0.0-m5", "section": "Parser antiquotations", "text": "Relaxed parsing further reduces need for explicit `$x:p` in macros.", "pull request": "1272"}
{"Version": "v4.0.0-m5", "section": "Computed fields", "text": "Inductives can define `[computedField]` for constant-time field access (values stored in constructor).", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "GetElem notation", "text": "`a[i]` is now `getElem a i (by get_elem_tactic)`. Also introduced `a[i]!` and `a[i]?` for panic/Option indexing.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Qualified recursion", "text": "Better support for qualified names in recursive declarations, e.g. `Nat.fact` inside a `namespace Nat` block.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "#eval CommandElabM", "text": "`#eval` supports `CommandElabM` monad for on-the-fly commands in user code.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "do-notation", "text": "Try elaborating do-blocks even if the expected type is unknown, allowing `#eval do IO.println ...` forms.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Linux backtrace", "text": "Panics on Linux print a backtrace by default. Disable via `LEAN_BACKTRACE=0`.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Parser grouping", "text": "Auto-insert `group(·)` where needed in `(...)+` combinators to avoid grammar conflicts.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Typed Macros", "text": "Syntax antiquotations track syntax kinds, reducing ill-formed expansions. (#1251 references)", "pull request": "1251"}
{"Version": "v4.0.0-m5", "section": "protected aliases", "text": "Alias of a protected definition is also protected. E.g. `Nat.double` → `Ex.double` is protected.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "IO.rand", "text": "`IO.rand` seeds from `IO.getRandomBytes`, more secure random initialization (#2 references?).", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "dot-notation/aliases", "text": "Improve dot-notation with namespace exports/aliases. E.g. `FinSet.union` as alias of `Set.union`.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "conv ext/enter", "text": "`ext` and `enter` conv tactics can go inside let-declarations in `conv at h => ...` blocks.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "conv zeta", "text": "New `zeta` conv tactic expands local let-declarations in the goal.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Namespace resolution", "text": "Improve how `open Tactic` can open both `Lean.Parser.Tactic` and `Lean.Elab.Tactic` (#1224 references).", "pull request": "1224"}
{"Version": "v4.0.0-m5", "section": "opaque command", "text": "Rename `constant` command to `opaque` for truly opaque definitions. Zulip discussion linked for details.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "induction/cases syntax", "text": "Support multiple left-hand-sides in a single alternative. Example: `cases v with | mk1 x | mk2 x => ...`", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "do-block indentation", "text": "`let/if` indentation in do-blocks is supported (#1120 references).", "pull request": "1120"}
{"Version": "v4.0.0-m5", "section": "Unnamed antiquotation", "text": "New `$_` antiquotation for syntax patterns without naming a placeholder.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Unused variables linter", "text": "Warn about unused variables in tactics. (#1159 references).", "pull request": "1159"}
{"Version": "v4.0.0-m5", "section": "Universe param check", "text": "Error if a decl body references a universe param not in its type or not explicit. E.g. hidden `PUnit.{u}` usage.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "subst_vars tactic", "text": "New `subst_vars` tactic to systematically substitute variable equalities.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "autoParam structure fields", "text": "Fix for lost `autoParam` in multiple inherited structure fields (#1158).", "pull request": "1158"}
{"Version": "v4.0.0-m5", "section": "[eliminator] attribute", "text": "Allows specifying a default recursor for `induction`/`cases`. Alternative to `using <recursor>` syntax.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "casesOn for recursion", "text": "Add support for `casesOn` in structural & well-founded recursion modules. E.g. writing definitions with tactics.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Option monad", "text": "`Option` is once again a monad (removed `OptionM`). (#279761084 references).", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "split tactic", "text": "Improved: can handle `match h : e with` even if `e` not a free variable. No more failing generalization step.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "match h : e encoding", "text": "Preserve `h : e` discriminants so tools like `split` can benefit from them. E.g. `match h : foo x with...`", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "exists tactic", "text": "`exists term1, term2, ...` supports comma-separated values in one statement.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "dsimp/dsimp!", "text": "Add tactics `dsimp` & `dsimp!` applying only rfl-theorems, preserving definitional equality in the result.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "match pattern binder info", "text": "Fix binder info for patterns using `[matchPattern]`-tagged defs like `Nat.add` in match expressions.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "structure field defaults", "text": "Now can depend on structure parameters. E.g. `n2 : Nat := 1 + i` is allowed.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "dsimp in simp", "text": "`dsimp` method in `simp` can apply `rfl`-theorems. Allows inlined expansions for better rewriting.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Auto-bound refinement", "text": "Auto-bound no longer captures the declaration's own name for an unbound variable. (#f → (#f is a var)??).", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Syntax highlight fix", "text": "No longer highlights some recursive calls as variables in inductive or function definitions.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "simp autoUnfold", "text": "`simp!`, `simp_arith!`, `simp_all!`, and `simp_all_arith!` auto-unfold recursive or match-based definitions.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "save tactic", "text": "`save` is a shorter alias for `checkpoint ...` in tactic scripts.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Remove constructor `{}`", "text": "Removed support for `{}` annotation in inductive & structure commands. Use new parameter/indices promotion.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "LSP improvements", "text": "Several fixes for go-to-definition in mutually rec defs, match patterns, pattern variables, etc.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "macro comb patterns", "text": "`macro ... xs:p* ...` has `xs : Array Syntax`. This ensures correct type for repeated parser combinators.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Ignored macro scopes", "text": "Syntax patterns ignore macro scopes in identifiers, improving pattern matching reliability.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "constructor param names", "text": "Improve auto implicit param naming for constructor arguments in mutual inductives (ex: `α` instead of `x`).", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Error message", "text": "Better error if constructor parameter's universe is too large. More consistent with other checks.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "for h : i in [start:stop]", "text": "Support iteration with index proof in `[start:stop]`. Eases termination proofs in loops over arrays, etc.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "case' tactic", "text": "`case'` is a variant of `case` that fails outright if the case doesn't exist, skipping fallback admission.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "stop tactic", "text": "Add `macro stop s:tacticSeq => repeat sorry`. Debug/placeholder tactic macro on discussion at Zulip.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Display goals", "text": "Don't display inaccessible proposition names if no forward dependencies. Only their types are shown.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "by_cases", "text": "Hypothesis name is optional in `by_cases p`, e.g. `by_cases p => ...` just references it as `this` or `_`. ", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "syntax vs. kind names", "text": "Rename node kinds: `numLit`→`num`, `charLit`→`char`, `nameLit`→`name`, `strLit`→`str`, `scientificLit`→`scientific` (#1090).", "pull request": "1090"}
{"Version": "v4.0.0-m5", "section": "checkpoint tactic", "text": "Experimental `checkpoint <tactic-seq>` for partial proof steps in large scripts.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "rename nativeDecide", "text": "Renamed tactic `nativeDecide` to `native_decide` for naming consistency.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Antiquotations", "text": "Now accepted in any syntax context. Removed `incQuotDepth` parser. Simplifies macro dev.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Local context cleanup", "text": "Remove `_discr := ...` or `h✝` from match patterns/branches, simplifying the local context.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "let/have pattern macros", "text": "Expansion ensures the goal references the new bindings, e.g. `let (a,b) := x` yields `f (a,b)` not `f x`.", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "Releases for aarch64", "text": "Add cross-compiled aarch64 Linux and macOS builds. (#1066, #1076 references)", "pull request": "none"}
{"Version": "v4.0.0-m5", "section": "doc/examples", "text": "Added tutorial-like examples using LeanInk+Alectryon for documentation.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "simp attributes", "text": "`simp` now supports user-defined simp-attributes. E.g. `register_simp_attr my_simp` for a custom set.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "Extended match syntax", "text": "Multiple LHS in single alternative, e.g. `| 0 | 1 => 1`. (#371 references).", "pull request": "371"}
{"Version": "v4.0.0-m4", "section": "#eval fallback", "text": "`#eval` tries to reduce the type further if no `Lean.MetaEval` is found initially. E.g. `def Foo := List Nat` now works.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "rw tactic eqn theorems", "text": "`rw` can apply auto-generated equation lemmas for a definition. E.g. `rw [List.length]` to step through eqns.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "Auto completion", "text": "Fuzzy matching for auto-completion (#1023).", "pull request": "1023"}
{"Version": "v4.0.0-m4", "section": "Function.field dot notation", "text": "`f.comp g` notation for function composition if `f : α→β`; done via `Function.field` arrow-type lookups.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "swift-like .<identifier>", "text": "Supports `.map .succ xs` etc. when a function type is expected (Zulip #944 references).", "pull request": "944"}
{"Version": "v4.0.0-m4", "section": "Folding", "text": "Added code folding support to language server (#1014).", "pull request": "1014"}
{"Version": "v4.0.0-m4", "section": "do-block let <pattern> := e | alt", "text": "Allow `let <pattern> := e | alt` in do-blocks for simple branching. Removes older partial expansions.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "Remove auto pure", "text": "No more 'auto' pure resolution. Must specify the monad or use type ascription if needed.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "congr theorems", "text": "No longer require all function args to be free vars on LHS. Partial argument usage is allowed.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "partially-applied congr", "text": "Allow partially applied congruence theorems for more general rewriting (#988 references).", "pull request": "988"}
{"Version": "v4.0.0-m4", "section": "Expected type heuristic", "text": "Reduce expected type if it's a metavariable before elaboration, to avoid incorrect postponement.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "Remove leanpkg", "text": "Deprecated `leanpkg` replaced by Lake as the package manager (#985).", "pull request": "985"}
{"Version": "v4.0.0-m4", "section": "Go-to-definition", "text": "Improve find-all-refs for newly introduced definitions. Also fix coverage for partial expansions.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "autoDecidable", "text": "Auto generated congr lemmas can cast proofs/`Decidable` instances (#988 references).", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "autoBoundImplicitLocal => autoImplicit", "text": "Renamed the option controlling auto-bound implicits to `autoImplicit`.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "contradiction tactic", "text": "`contradiction` closes the goal if `False.elim` is in the target or a local hypothesis.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "byCases => by_cases", "text": "Renamed tactic `byCases` to `by_cases` for naming convention consistency.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "Local instance in patterns", "text": "Typeclass resolution can use local instances from patterns, e.g. `(⟨_, inst⟩ :: as).", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "motive in match", "text": "Now `(motive := (args) → ...)` syntax instead of whitespace-based. E.g. `match (motive := ...) x, rfl with ...`", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "generalizing = true by default", "text": "`match` defaults to `(generalizing := true)` even if the result type is not a Prop. E.g. no extra annotation needed.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "PSum usage", "text": "Mutually recursive definitions use `PSum` instead of `Sum` for well-founded rec. (#??) no PR # here.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "Parametric well-founded", "text": "Better support for parametric well-founded relations (#1017).", "pull request": "1017"}
{"Version": "v4.0.0-m4", "section": "while/do-block", "text": "Add macros `while <cond>` / `repeat <do>` / `repeat <do> until <cond>` for partial/do usage only.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "arith in `simp`", "text": "New `arith` option in `Simp.Config`. `simp_arith` includes Nat linear arithmetic rewriting.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "fail tactic", "text": "`fail <message>` tactic that always fails with a user-provided error text.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "acyclicity in dep elim", "text": "Check acyclicity in dependent elimination, addressing #1022 potentially.", "pull request": "1022"}
{"Version": "v4.0.0-m4", "section": "trace tactic", "text": "Add `trace <string>` tactic for debugging messages within proofs.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "SizeOf for (Unit→α)", "text": "Add nontrivial `SizeOf` for function types `Unit→α` and in user-defined inductives with delayed fields.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "Guess simpler WF", "text": "Try simple well-founded relations automatically for recursion. E.g. no extra `termination_by` needed for array loops.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "for x in xs do", "text": "Add `for h : x in xs do ...` meaning `h : x ∈ xs`. Useful for termination of iteration-based definitions.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "Auto-implicit chaining", "text": "Unassigned metavariables in auto-implicit types become fresh auto-implicit locals. E.g. `HasType` example with `n`.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "promote prefix to parameters", "text": "Fixed prefix of inductive family indices is promoted to parameters if they do not vary. E.g. `Sublist`, `Lst` examples.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "Auto-implicit rec", "text": "Chaining unassigned meta in index types now fosters correct type injection for families (#??).", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "Eliminate autoParam/optParam in recursors", "text": "Recursor minor premises & structure projections no longer carry autoParam/optParam overhead.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "Overloaded notation in patterns", "text": "Allowed if each alternative has the same pattern variable set. E.g. `::` for List/Vector in different contexts.", "pull request": "none"}
{"Version": "v4.0.0-m4", "section": "Swift-like dot syntax", "text": "Introducing `.<ident>` notation. Infers namespace from expected type. E.g. `.ok x`, `.error \"...\"`", "pull request": "944"}