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.
This PR fixes a bug in the constant folding for the `Nat.ble` and
`Nat.blt` function in the old code generator, leading to a
miscompilation.
Closes#6086
This PR introduces date and time functionality to the Lean 4 Std.
Breaking Changes:
- `Lean.Data.Rat` is now `Std.Internal.Rat` because it's used by the
DateTime library.
---------
Co-authored-by: Markus Himmel <markus@himmel-villmar.de>
Co-authored-by: Mac Malone <tydeu@hatpress.net>
This PR 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.
Closes#6011
This PR 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`.
The tag of trace messages has also been changed from `_traceMsg` to the
more friendly `trace`.
This PR 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`:
```lean
example (p : Nat × Nat) : p = p := by
change _ = ⟨_, _⟩ -- used to work (yielding `p = (p.fst, p.snd)`), now it doesn't
change ⟨_, _⟩ = _ -- never worked
```
As such, this is a breaking change; you may need to adjust expressions
to include additional implicit arguments.
This PR implements conversion functions from `Bool` to all `UIntX` and
`IntX` types.
Note that `Bool.toUInt64` already existed in previous versions of Lean.
This PR changes the signature of `Array.get` to take a Nat and a proof,
rather than a `Fin`, for consistency with the rest of the (planned)
Array API. Note that because of bootstrapping issues we can't provide
`get_elem_tactic` as an autoparameter for the proof. As users will
mostly use the `xs[i]` notation provided by `GetElem`, this hopefully
isn't a problem.
We may restore `Fin` based versions, either here or downstream, as
needed, but they won't be the "main" functions.
---------
Co-authored-by: David Thrane Christiansen <david@davidchristiansen.dk>
This PR 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.
Features:
- Only parents that are not ancestors of other parents get instances.
This allows "discretionary" indirect parents to be inserted for the
purpose of computing strict resolution orders when
`structure.strictResolutionOrder` is enabled, without having an impact
on typeclass synthesis.
- Non-subobject projections are now theorems if the parent is a
proposition. These are also no longer `@[reducible]`.
Closes#2905
This PR fixes `bv_decide`'s embedded constraint substitution to generate
correct counter examples in the corner case where duplicate theorems are
in the local context.
This PR 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.
Beyond this I also added some profiling infra structure for the passes.
This PR 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:
```lean
example {x : BitVec 16} : x / (BitVec.twoPow 16 2) = x >>> 2 := by bv_normalize
example {x : BitVec 16} : x / (BitVec.ofNat 16 8) = x >>> 3 := by bv_normalize
```
This PR changes the signature of `Array.set` to take a `Nat`, and a
tactic-provided bound, rather than a `Fin`.
Corresponding changes (but without the auto-param) for `Array.get` will
arrive shortly, after which I'll go more pervasively through the Array
API.
