This PR 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.
This PR fixes a bug in structure instance field completion that caused
it to not function correctly for bracketed structure instances written
in Mathlib style.
This PR 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`.
Closes#5064
This PR modifies structure instance notation and `where` notation to use
the same notation for fields. Structure instance notation now admits
binders, type ascriptions, and equations, and `where` notation admits
full structure lvals. Examples of these for structure instance notation:
```lean
structure PosFun where
f : Nat → Nat
pos : ∀ n, 0 < f n
def p : PosFun :=
{ f n := n + 1
pos := by simp }
def p' : PosFun :=
{ f | 0 => 1
| n + 1 => n + 1
pos := by rintro (_|_) <;> simp }
```
Just like for the structure `where` notation, a field `f x y z : ty :=
val` expands to `f := fun x y z => (val : ty)`. The type ascription is
optional.
The PR also is setting things up for future expansion. Pending some
discussion, in the future structure/`where` notation could have have
embedded `where` clauses; rather than `{ a := { x := 1, y := z } }` one
could write `{ a where x := 1; y := z }`.
This PR 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.
The default setting does change the existing behavior. Users can use
`simp -implicitDefEqProofs` to force `simp` to create a proof term for
`rfl`-theorems. This can positively impact proof checking time in the
kernel.
This PR also fixes an issue in the `split` tactic that has been exposed
by this feature. It was looking for `split` candidates in proofs and
implicit arguments. See new test for issue exposed by the previous
feature.
---------
Co-authored-by: Kim Morrison <kim@tqft.net>
This PR adds the builtin simproc `USize.reduceToNat` which reduces the
`USize.toNat` operation on literals less than `UInt32.size` (i.e.,
`4294967296`).
This PR deprecates `Fin.ofNat` in favour of `Fin.ofNat'` (which takes an
`[NeZero]` instance, rather than returning an element of `Fin (n+1)`).
After leaving the deprecation warning in place for some time, we will
then rename `ofNat'` back to `ofNat`.
This PR makes stricter requirements for the `@[deprecated]` attribute,
requiring either a replacement identifier as `@[deprecated bar]` or
suggestion text `@[deprecated "Past its use by date"]`, and also
requires a `since := "..."` field.
This PR changes how generalized field notation ("dot notation") resolves
the function. The new resolution rule is that if `x : S`, then `x.f`
resolves the name `S.f` relative to the root namespace (hence it now
affected by `export` and `open`). Breaking change: aliases now resolve
differently. Before, if `x : S`, and if `S.f` is an alias for `S'.f`,
then `x.f` would use `S'.f` and look for an argument of type `S'`. Now,
it looks for an argument of type `S`, which is more generally useful
behavior. Code making use of the old behavior should consider defining
`S` or `S'` in terms of the other, since dot notation can unfold
definitions during resolution.
This also fixes a bug in explicit-mode generalized field notation
(`@x.f`) where `x` could be passed as the wrong argument. This was not a
bug for explicit-mode structure projections.
Closes#3031. Addresses the `Function` namespace issue in #1629.
This PR changes the signature of `Array.swap`, so it takes `Nat`
arguments with tactic provided bounds checking. It also renames
`Array.swap!` to `Array.swapIfInBounds`.
This PR 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.
Note: there is still the limitation that parents that are not
represented as subobjects do not themselves provide instances to other
parents.
This PR 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.
This PR 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.
closes#6067
This PR adds core metaprogramming functions for forking off background
tasks from elaboration such that their results are visible to reporting
and the language server
This PR adds support for `structure` in `mutual` blocks, allowing
inductive types defined by `inductive` and `structure` to be mutually
recursive. The limitations are (1) that the parents in the `extends`
clause must be defined before the `mutual` block and (2) mutually
recursive classes are not allowed (a limitation shared by `class
inductive`). There are also improvements to universe level inference for
inductive types and structures. Breaking change: structure parents now
elaborate with the structure in scope (fix: use qualified names or
rename the structure to avoid shadowing), and structure parents no
longer elaborate with autoimplicits enabled.
Internally, this is a large refactor of both the `inductive` and
`structure` commands. Common material is now in
`Lean.Elab.MutualInductive`, and each command plugs into this mutual
inductive elaboration framework with the logic specific to the
respective command. For example, `structure` has code to add projections
after the inductive types are added to the environment.
Closes#4182
This PR modifies the signature of the functions `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.
This PR fixes a non-termination bug that occurred when generating the
match-expression splitter theorem. The bug was triggered when the proof
automation for the splitter theorem repeatedly applied `injection` to
the same local declaration, as it could not be removed due to forward
dependencies. See issue #6065 for an example that reproduces this issue.
closes#6065
This PR does the same fix as #6104, but such that it doesn't break the
test/the file in `Plausible`. This is done by not creating unused let
binders in metavariable types that are made by `elimMVar`. (This is also
a positive thing for users looking at metavariable types, for example in
error messages)
We get rid of `skipAtMostNumBinders`. This function was originally
defined for the purpose of making this test work, but it is a hack
because it allows cycles in the metavariable context.
It would make sense to split these changes into 2 PRs, but I combined
them here to show that the combination of them closes#6013 without
breaking anything
Closes#6013
This PR replaces `Array.feraseIdx` and `Array.insertAt` with
`Array.eraseIdx` and `Array.insertIdx`, both of which take a `Nat`
argument and a tactic-provided proof that it is in bounds. We also have
`eraseIdxIfInBounds` and `insertIdxIfInBounds` which are noops if the
index is out of bounds. We also provide a `Fin` valued version of
`Array.findIdx?`. Together, these quite ergonomically improve the array
indexing safety at a number of places in the compiler/elaborator.
This PR 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.
Example output for `#print Monad`:
```
class Monad.{u, v} (m : Type u → Type v) : Type (max (u + 1) v)
number of parameters: 1
parents:
Monad.toApplicative : Applicative m
Monad.toBind : Bind m
fields:
Functor.map : {α β : Type u} → (α → β) → m α → m β
Functor.mapConst : {α β : Type u} → α → m β → m α
Pure.pure : {α : Type u} → α → m α
Seq.seq : {α β : Type u} → m (α → β) → (Unit → m α) → m β
SeqLeft.seqLeft : {α β : Type u} → m α → (Unit → m β) → m α
SeqRight.seqRight : {α β : Type u} → m α → (Unit → m β) → m β
Bind.bind : {α β : Type u} → m α → (α → m β) → m β
constructor:
Monad.mk.{u, v} {m : Type u → Type v} [toApplicative : Applicative m] [toBind : Bind m] : Monad m
resolution order:
Monad, Applicative, Bind, Functor, Pure, Seq, SeqLeft, SeqRight
```
Suggested by Floris van Doorn [on
Zulip](https://leanprover.zulipchat.com/#narrow/channel/270676-lean4/topic/.23print.20command.20for.20structures/near/482503637).
This PR fixes a bug at the definitional equality test (`isDefEq`). At
unification constraints of the form `c.{u} =?= c.{v}`, it was not trying
to unfold `c`. This bug did not affect the kernel.
closes#6117
This PR adds a case to `Level.geq` that is present in the kernel's level
`is_geq` procedure, making them consistent with one another.
This came up during testing of `lean4lean`. Currently `Level.geq`
differs from `level::is_geq` in the case of `max u v >= imax u v`. The
elaborator function is overly pessimistic and yields `false` on this
while the kernel function yields true. This comes up concretely in the
`Trans` class:
```lean
class Trans (r : α → β → Sort u) (s : β → γ → Sort v) (t : outParam (α → γ → Sort w)) where
trans : r a b → s b c → t a c
```
The type of this class is `Sort (max (max (max (max (max (max 1 u) u_1)
u_2) u_3) v) w)` (where `u_1 u_2 u_3` are the levels of `α β γ`), but if
you try writing that type explicitly then the `class` command fails.
Omitting the type leaves the `class` to infer the universe level (the
command assumes the level is correct, and the kernel agrees it is), but
including the type then the elaborator checks the level inequality with
`Level.geq` and fails.
---------
Co-authored-by: Kyle Miller <kmill31415@gmail.com>
This PR fixes a bug where structural recursion did not work when indices
of the recursive argument appeared as function parameters in a different
order than in the argument's type's definition.
Fixes#6015.
This PR liberalizes atom rules by allowing `''` to be a prefix of an
atom, after #6012 only added an exception for `''` alone, and also adds
some unit tests for atom validation.
This PR 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`.
This PR fixes a stack overflow caused by a cyclic assignment in the
metavariable context. The cycle is unintentionally introduced by the
structure instance elaborator.
closes#3150
This PR 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:
```lean
example (x y z : Nat) : x + y = z := by
change ?a = _
let w := ?a
-- now `w : Nat := x + y`
```
This PR adds raw transmutation of floating-point numbers to and from
`UInt64`. Floats and UInts share the same endianness across all
supported platforms. The IEEE 754 standard precisely specifies the bit
layout of floats. Note that `Float.toBits` is distinct from
`Float.toUInt64`, which attempts to preserve the numeric value rather
than the bitwise value.
closes#6071
This PR 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)`.
Any notations with precedence greater than or equal to `maxPrec` do not
receive such discretionary parentheses, since this precedence level is
considered to be infinity.
This option was a feature in the Lean 3 community edition.
