This PR adds an experimental `cbv` tactic that can be invoked from
`conv` mode. The tactic is not suitable for production use and an
appropriate warning is displayed.
This PR moves the `PredTrans.apply` structure field into a separate
`def`. Doing so improves kernel reduction speed because the kernel is
less likely to unfold definitions compared to structure field
projections. This causes minor shifts in `simp` normal forms.
This PR shifts the conversion from LCNF mono to lambda pure into the
LCNF impure phase. This is preparatory work for the upcoming refactor of
IR into LCNF impure.
The LCNF impure phase differs from the other LCNF phases in two crucial
ways:
1. I decided to have `Decl.type` be the result type as opposed to an
arrows from the parameter types to the result type. This is done because
impure does not have a notion of arrows anymore so keeping them around
for this one particular purpose would be slightly odd.
2. In order to avoid cluttering up the olean size LCNF impure saves only
the signature persistently to the disk. This is possible because we no
longer have inlining/specialization at this point of compilation so all
we need is typing information (and potentially other environment
extensions) to guide our analyses.
This PR implements RFC #12216: native computation (`native_decide`,
`bv_decide`) is represented in the logic as one axiom per computation,
asserting the equality that was obtained from the native computation.
`#print axiom` will no longer show `Lean.trustCompiler`, but rather the
auto-generated names of these axioms (with, for example,
`._native.bv_decide.` in the name). See the RFC for more information.
This PR introduces a common MetaM helper (`nativeEqTrue`) used by
`native_decide` and `bv_decide` alike that runs the computation and then
asserts the result using an axiom.
It also deprecated the `ofReduceBool` axioms etc.
Not included in this PR is infrastructure for enumerating these axioms,
prettier `#print axioms` (should we want his) and tactic concurrency.
Fixes#12216.
This PR refines upon #12106, by setting the `isRecursive` env extension
after adding the declaration, but before processing attributes like
`macro_inline` that want to look at the flag. Fixes#12268.
This PR fixes a unification issue that appeared in
`Lean.Meta.MkIffOfInductiveProp` machinery that was upstreamed from
Mathlib. Inside of `toInductive`, wrong free variables were passed,
which made it impossible to perform a unification in certain cases.
Closes#12215
This PR makes several small improvements to the list/array/vector API:
* It fixes typos in `Init.Core`.
* It adds `List.isSome_min_iff` and `List.isSome_max_iff`.
* It adds `grind` and `simp` annotations to various previously
unannotated lemmas.
* It adds lemmas for characterizing `∃ x ∈ xs, P x` using indices as `∃
(i : Nat), ∃ hi, P (xs[i])`, and similar universally quantified lemmas:
`exists_mem_iff_exists_getElem` and `forall_mem_iff_forall_getElem`.
* It adds `Vector.toList_zip`.
* It adds `map_ofFn` and `ofFn_getElem` for lists/arrays/vectors.
This PR adds the new transparency setting `@[instance_reducible]`. We
used to check whether a declaration had `instance` reducibility by using
the `isInstance` predicate. However, this was not a robust solution
because:
- We have scoped instances, and `isInstance` returns `true` only if the
scope is active.
- We have auxiliary declarations used to construct instances manually,
such as:
```lean
def lt_wfRel : WellFoundedRelation Nat
```
`isInstance` also returns `false` for this kind of declaration.
In both cases, the declaration may be (or may have been) used to
construct an instance, but `isInstance`
returns `false`. Thus, we claim it is a mistake to check the
reducibility status using `isInstance`.
`isInstance` indicates whether a declaration is available for the type
class resolution mechanism,
not its transparency status.
**We are decoupling whether a declaration is available for type class
resolution from its transparency status.**
**Remak**: We need a update stage0 to complete this feature.
---------
Co-authored-by: Sebastian Ullrich <sebasti@nullri.ch>
This PR fixes a bug on Windows with `IO.Process.spawn` where setting an
environment variable to the empty string would not set the environment
variable on the subprocess.
This PR fixes a bug where `grind?` suggestions would not include
parameters using local variable dot notation (e.g.,
`cs.getD_rightInvSeq` where `cs` is a local variable). These parameters
were incorrectly filtered out because the code assumed all ident params
resolve to global declarations. In fact, local variable dot notation
produces anchors that need the original term to be loaded during replay,
so they must be preserved in the suggestion.
Closes#12185🤖 Prepared with Claude Code
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
This PR gives a simpler semantics to `noncomputable`, improving
predictability as well as preparing codegen to be moved into a separate
build step without breaking immediate generation of error messages.
Specifically, `noncomputable` is now needed whenever an axiom or another
`noncomputable` def is used by a def except for the following special
cases:
* uses inside proofs, types, type formers, and constructor arguments
corresponding to (fixed) inductive parameters are ignored
* uses of functions marked `@[extern]/@[implemented_by]/@[csimp]` are
ignored
* for applications of a function marked `@[macro_inline]`,
noncomputability of the inlining is instead inspected
# Breaking change
After this change, more `noncomputable` annotations than before may be
required in exchange for improved future stability.
This PR introduces a phase separation to the LCNF IR. This is a
preparation for the merge of
the old `Lean.Compiler.IR` and the new `Lean.Compiler.LCNF` framework.
The change parametrizes all relevant `LCNF` data structures over a
`Purity` parameter and
additionally carries around proofs that the `Purity` has certain values,
depending on what's
required. This is done as opposed to indexing the types over `Purity`
because we do (almost) never
have to store the `Purity` value for phase generic structures this way.
This PR reverts a lot of the changes done in #8308. We practically
encountered situations such as:
```
fun y (z) :=
let x := inst
mkInst x z
f y
```
Where the instance puller turns it into:
```
let x := inst
fun y (z) :=
mkInst x z
f y
```
The current heuristic now discovers `x` being in scope at the call site
of `f` and being used under a binder in `y` and thus blocks pulling in
`x` to the specialization, abstracting over an instance.
According to @zwarich this was done at the time either due to observed
stack overflows or pulling in computation into loops. With the current
configuration for abstraction in specialization it seems rather unlikely
that we pull in a non trivial computation into a loop with this. We also
practically didn't observe stack overflows in our tests or benchmarks.
Cameron speculates that the issues he observed might've been fixed
otherwise by now.
Crucial note: Deciding not to abstract over ground terms *might* cause
us to pull in computationally intensive ground terms into a loop. We
could decide to weaken this to just instance terms though of course even
computing instances might end up being non-trivial.
This PR updates docstrings and function signatures in order to complete
the transition from `Iter.Partial` to `Iter.Total` (extrinsically
terminating by default). It also deprecates `allowNontermination` and
adds `Iter.Total.atIdxSlow?`.
This PR ensures `dsimp` does not "simplify" instances by default. The
old behavior can be retrieved by using
```
set_option backward.dsimp.instances true
```
Applying `dsimp` to instances creates non-standard instances, and this
creates all sorts of problems in Mathlib.
This modification is similar to
```
set_option backward.dsimp.proofs true
```
---------
Co-authored-by: Kim Morrison <kim@tqft.net>
Co-authored-by: Claude <noreply@anthropic.com>
This PR fixes how we determine whether a function parameter is an
instance.
Previously, we relied on binder annotations (e.g., `[Ring A]` vs `{_ :
Ring A}`)
to make this determination. This is unreliable because users
legitimately use
`{..}` binders for class types when the instance is already available
from
context. For example:
```lean
structure OrdSet (α : Type) [Hashable α] [BEq α] where
...
def OrdSet.insert {_ : Hashable α} {_ : BEq α} (s : OrdSet α) (a : α) : OrdSet α :=
...
```
Here, `Hashable` and `BEq` are classes, but the `{..}` binder is
intentional, the
instances come from `OrdSet`'s parameters, so type class resolution is
unnecessary.
The fix checks the parameter's *type* using `isClass?` rather than its
syntax, and
caches this information in `FunInfo`. This affects several subsystems:
- **Discrimination trees**: instance parameters should not be indexed
even if marked with `{..}`
- **Congruence lemma generation**: instances require special treatment
- **`grind` canonicalizer**: must ensure canonical instances
**Potential regressions**: automation may now behave differently in
cases where it
previously misidentified instance parameters. For example, a rewrite
rule in `simp` that was
not firing due to incorrect indexing may now fire.
---------
Co-authored-by: Kim Morrison <kim@tqft.net>
Co-authored-by: Claude <noreply@anthropic.com>
This PR removes the LCNF testing framework. Unfortunately it never got
used much and porting it to
the extended LCNF structure now would be a bit of effort that would
ultimately be in vain.
This PR adds `mkBackwardRuleFromExpr` to create backward rules from
expressions, complementing the existing `mkBackwardRuleFromDecl` which
only works with declaration names.
The new function enables creating backward rules from partially applied
terms. For example, `mkBackwardRuleFromExpr (mkApp (mkConst
``Exists.intro [1]) Nat.mkType)` creates a rule for `Exists.intro` with
the type parameter fixed to `Nat`, leaving only the witness and proof as
subgoals.
The `levelParams` parameter supports universe polymorphism: when
creating a rule like `Prod.mk Nat` that should work at multiple universe
levels, the caller specifies which level parameters remain polymorphic.
The pattern's universe variables are then instantiated appropriately at
each application site.
Also refactors `Pattern.lean` to share code between declaration-based
and expression-based pattern creation, extracting `mkPatternFromType`
and `mkEqPatternFromType` as common helpers.
This PR activates `getElem?_pos` more aggressively, triggered by `c[i]`.
- [x] depends on: #12176🤖 Prepared with Claude Code
---------
Co-authored-by: Claude <noreply@anthropic.com>
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 regression tests that catch issues where structures/classes
with class-typed fields produce HEq goals in `congr` instead of handling
Prop fields automatically.
Both tests pass on v4.28.0-rc1 (before isInstance detection changes).
## Test 1: Structure extending classes (mirrors Mathlib's GroupTopology)
```lean
structure MyGroupTopology (α : Type) extends MyTopology α, IsContinuousMul α
theorem MyGroupTopology.toMyTopology_injective {α : Type} :
Function.Injective (MyGroupTopology.toMyTopology : MyGroupTopology α → MyTopology α) := by
intro f g h
cases f
cases g
congr
```
**Failure mode:** `⊢ toIsContinuousMul✝¹ ≍ toIsContinuousMul✝`
## Test 2: Class with explicit class-typed field (mirrors Mathlib's
PseudoEMetricSpace)
```lean
class MyMetricSpace (α : Type) extends MyDist α where
dist_self : ∀ x : α, dist x x = 0
toMyUniformity : MyUniformity α -- explicit class-typed field (NOT from extends)
uniformity_dist : toMyUniformity.uniformity (fun x y => dist x y = 0)
protected theorem MyMetricSpace.ext {α : Type} {m m' : MyMetricSpace α}
(h : m.toMyDist = m'.toMyDist) (hU : m.toMyUniformity = m'.toMyUniformity) : m = m' := by
cases m
cases m'
congr 1 <;> assumption
```
**Failure mode:** `⊢ dist_self✝¹ ≍ dist_self✝` and `⊢ uniformity_dist✝¹
≍ uniformity_dist✝`
## Context
These tests are related to #12172, which changes instance parameter
detection from binder-based to `isClass?`-based. That change can affect
how structure fields are classified in congruence lemma generation.
🤖 Prepared with Claude Code
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
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 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 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.
