This PR fixes a bug where delayed E-match theorem instances could cause
uniqueId collisions in the instance tracking map.
The `uniqueId` for theorem instances is generated using `numInstances`,
but this counter was only bumped for immediately activated instances
(`.ready` case), not for delayed instances (`.next` case). This caused
ID collisions:
1. Theorem A matches, becomes delayed, gets `uniqueId = N`
2. Counter isn't bumped (stays at N)
3. Theorem B matches next, gets `uniqueId = N` (same!)
4. B's entry overwrites A's entry in `instanceMap`
5. A's tracking is lost
This manifested as `grind?` and `finish?` producing `instantiate approx`
(meaning "we couldn't determine which theorems to use") instead of
proper `instantiate only [...]` with specific theorem lists.
The fix bumps `numInstances` for delayed instances too, ensuring each
theorem instance gets a truly unique ID.
🤖 Prepared with Claude Code
Co-authored-by: Claude <noreply@anthropic.com>
This PR adds `prefix_map_iff_of_injective` and
`suffix_map_iff_of_injective` lemmas to Init.Data.List.Nat.Sublist.
These lemmas establish that if a function `f` is injective, then the
prefix and suffix relations are preserved under mapping (e.g., `l₁.map f
<+: l₂.map f ↔ l₁ <+: l₂`). These additions complement the existing
index-based lemmas in this file and allow for simpler structural proofs
without resorting to `take`, `drop`, or manual index manipulation.
This PR adds the function `Std.Iter.first?` and proves the specification
lemma `Std.Iter.first?_eq_match_step` if the iterator is productive.
The monadic variant on `Std.IterM` is also provided.
We use this new function to fix the default implementation for
`startsWith` and `dropPrefix` on `String` patterns, which used to fail
if the searcher returned a `skip` at the beginning. None of the patterns
we ship out of the box were affected by this, but user-defined patterns
were vulnerable.
---------
Co-authored-by: Paul Reichert <6992158+datokrat@users.noreply.github.com>
This PR scopes the `simp` attribute on `FamilyOut.fam_eq` to the `Lake`
namespace. The lemma has a very permissive discrimination tree key
(`_`), so when `Lake.Util.Family` is transitively imported into
downstream projects, it causes `simp` to attempt this lemma on every
goal, leading to timeouts.
See
https://leanprover.zulipchat.com/#narrow/channel/270676-lean4/topic/Lake.20.60FamilyOut.2Efam_eq.60.20leads.20to.20timeouts.3F🤖 Prepared with Claude Code
---------
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Mac Malone <tydeu@hatpress.net>
This PR fixes a comment that said "implicit arguments" when the code
actually checks `isInstImplicit`, which is specifically for instance
implicit arguments (`[...]` binders), not all implicit arguments.
🤖 Prepared with Claude Code
Co-authored-by: Claude <noreply@anthropic.com>
This PR bumps the version to 4.29.0 to begin the next development cycle
after v4.28.0-rc1.
🤖 Prepared with Claude Code
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
This PR adds `Option.of_wp_eq` and `Except.of_wp_eq`, similar to the
existing `Except.of_wp`. `Except.of_wp` is deprecated because applying
it requires prior generalization, at which point it is more convenient
to use `Except.of_wp_eq`.
This PR makes the compiler produce C code that statically initializes
close terms when possible. This change reduces startup time as the terms
are directly stored in the binary instead of getting computed at
startup.
The set of terms currently supported by this mechanism are:
- string literals
- ctors called with other statically initializeable arguments
- `Name.mkStrX` and other `Name` ctors as they require special support
due to their computed field and occur frequently due to name literals.
In core there are currently 152,524 closed terms and of these 103,929
(68%) get initialized statically with this PR. The remaining 48585 ones
are not extracted because they use (potentially transitively) various
non trivial pieces of code like `stringToMessageData` etc. We might
decide to add special support for these in the future but for the moment
this feels like it's overfitting too much for core.
This extracts a `postCallback` helper so that only the actual callback
is inlined.
Part of the motivation here is to exclude these tracing frames from
flame graph profiles.
---------
Co-authored-by: Sebastian Ullrich <sebasti@nullri.ch>
This PR adds `simpTelescope`, a simproc that simplifies telescope
binders (`have`-expression values and arrow hypotheses) but not the
final body. This is useful for simplifying targets before introducing
hypotheses.
This PR adds `simpArrowTelescope`, a simproc that simplifies telescopes
of non-dependent arrows (p₁ → p₂ → ... → q) while avoiding quadratic
proof growth.
When using `Expr.forallE` to represent nested implications, each nesting
level bumps de Bruijn indices in subterms, destroying sharing even with
hash-consing. For example, a free variable `x` gets different de Bruijn
representations at each depth, causing proof terms to grow.
`simpArrowTelescope` works by:
- Converting arrows to `Arrow p q` (a definitional wrapper)
- Simplifying each component
- Converting back to `→` form
Since `Arrow` arguments are not under binders, subterms remain identical
across nesting levels and can be shared.
The `simp_4` benchmark demonstrates the improvement:
With `forallE`: ~160ms, proof_size ≈ 173k
With `Arrow`: ~43ms, proof_size ≈ 16k
Tradeoff: `simpArrowTelescope` misses simplifications that depend on the
arrow structure (e.g., `p → p` to `True`), since post-methods aren't
applied to intermediate arrows. Thus, it is not used by default. to use
it, one has to set `simpArrowTelescope` as a `pre`-method.
This PR reverts #12000, which introduced a regression where `simp`
incorrectly rejects valid rewrites for perm lemmas.
The issue is that `NameGenerator.mkChild` creates names that don't
maintain the ordering assumption used by `acLt` for perm lemma
decisions. For example, after the change:
- Child generator creates names like `_uniq.102.2`
- Parent continues with `_uniq.7`
- But `Name.lt (.num (.num `_uniq 102) 2) (.num `_uniq 7)` is true
This causes fvars created later (in async tasks) to compare as smaller
than fvars created earlier, breaking the assumption that later fvars
compare greater according to `Name.lt`.
Fixes#12136.
🤖 Prepared with [Claude Code](https://claude.com/claude-code)
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
This PR adds an API for building symbolic simulation engines and
verification
condition generators that leverage `grind`. The API wraps `Sym`
operations to
work with `grind`'s `Goal` type, enabling lightweight symbolic execution
while
carrying `grind` state for discharge steps.
New operations on `Goal`:
- `mkGoal`: create a `Goal` from an `MVarId`
- `introN`, `intros`: introduce binders
- `apply`: apply backward rules
- `simp`, `simpIgnoringNoProgress`: simplify using `Sym.Simp`
- `internalize`, `internalizeAll`: add hypotheses to the E-graph
- `grind`: attempt to close the goal using `grind`
- `assumption`: close by matching a hypothesis
A new test demonstrates the API on a stateful program with conditionals,
using `grind` to discharge arithmetic side conditions.
This PR fixes a bug introduced in #12086 where a `lake build :release
--no-build` would exit with code 1 rather than the `--no-build ` code 3.
Now both the bug from #12086 and this bug are fixed.
This PR fixes an issue that may sporadically trigger ASAN to got into a
deadlock when running a subprocess through the `IO.Process.spawn`
framework.
The general issue here is that we run `fork()` and then perform an
allocation in the child before going to `execvp` (for allocating the
arguments to `execvp`). As it turns out, doing this can cause a race
condition in ASAN that ultimately causes a deadlock in the child. This
was fixed upstream but then rolled back (see
https://github.com/google/sanitizers/issues/774). Thus, we must avoid
allocating any memory in between `fork` and `execvp`.
This PR fixes the verso hint that appears when using `sorry` in an
example block. It previously said: `` The `+error` flag indicates that
warnings are expected: +warning `` This PR replaces `error` with
`warning`. Fixes#12064
This PR revives the ability to specify modules in dependencies via the
basic `+mod` target key.
Implementation-wise, this removes deprecation of `BuildKey.module` and
once again uses it for `+mod` target keys. It also adds a test for
depending on a module of a dependency via `needs`.
This PR fixes the `lake query` output for targets which produce an
`Array` or `List` of a value with a custom `QueryText` or `QueryJson`
instance (e.g., `deps` and `transDeps`).
This PR implements iteration over ranges for `Fin` and `Char`.
To this end, we introduce machinery for pulling back lawfulness of
`UpwardEnumerable` along an injective map and study the function
`Char.ordinal : Char -> Fin Char.numCodePoints`.
This PR fixes two Lake cache issues: a bug where a failed upload would
not produce an error and a mistake in the `--wfail` checks of the cache
commands.
This PR fixes a bug where a `lake build --no-build` would exit with code
`3` if the optional job to fetch a GitHub or Reservoir release for a
package failed (even if nothing else needed rebuilding).