This PR reworks the `simp` set around the `Id` monad, to not elide or
unfold `pure` and `Id.run`
In particular, it stops encoding the "defeq abuse" of `Id X = X` in the
statements of theorems, instead using `Id.run` and `pure` to pass back
and forth between these two spellings. Often when writing these with
`pure`, they generalize to other lawful monads; though such changes were
split off to other PRs.
This fixes the problem with the current simp set where `Id.run (pure x)`
is simplified to `Id.run x`, instead of the desirable `x`.
This is particularly bad because the` x` is sometimes inferred with type
`Id X` instead of `X`, which prevents other `simp` lemmas about `X` from
firing.
Making `Id` reducible instead is not an option, as then the `Monad`
instances would have nothing to key on.
---------
Co-authored-by: Sebastian Graf <sg@lean-fro.org>
Co-authored-by: Kim Morrison <kim@tqft.net>
Co-authored-by: Paul Reichert <6992158+datokrat@users.noreply.github.com>
This PR ensures that names suggested by tactics like `simp?` are not
shadowed by auxiliary declarations in the local context and that names
of `let rec` and `where` declarations are correctly resolved in tactic
blocks.
This PR contains the following potentially breaking changes:
* Moves the `auxDeclToFullName` map from `TermElab.Context` to
`LocalContext`.
* Refactors `Lean.Elab.Term.resolveLocalName : Name → TermElabM …` to
`Lean.resolveLocalName [MonadResolveName m] [MonadEnv m] [MonadLCtx m] :
Name → m …`.
* Refactors the `TermElabM` action `Lean.Elab.Term.withAuxDecl` to a
monad-polymorphic action `Lean.Meta.withAuxDecl`.
* Adds an optional `filter` argument to `Lean.unresolveNameGlobal`.
Closes#6706, closes#7073.
This PR moves away from using `List.get` / `List.get?` / `List.get!` and
`Array.get!`, in favour of using the `GetElem` mediated getters. In
particular it deprecates `List.get?`, `List.get!` and `Array.get?`. Also
adds `Array.back`, taking a proof, matching `List.getLast`.
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.
@Kha I was tired of writing `arbitrary _` :)
There 0 places in the stdlib where the type needs to be provided.
If in the future we need to specify the type we can use
`arbitrary (α := <type>)`
