This is a quite substantial tactic.
It also includes the infamour `NatCast` typeclass (which I've equipped
with a module-doc). I wasn't at all sure where that should live, so it
is currently randomly in `Lean/Elan/Tactic/NatCast.lean`: presumably if
we're doing this it will go somewhere in `Init`.
---------
Co-authored-by: Leonardo de Moura <leomoura@amazon.com>
When updating Std, be careful that not every lemma has been upstreamed,
so we need to be careful to only delete things that have already been
declared.
Before the `zeta` / `zetaDelta` split, `dsimp` was performing `zeta`
by going inside of a `let`-expression, performing `zetaDelta`, and
then removing the unused `let`-expression.
This is pretty big PR that upstreams all of Std.Data.Int.Init in one go.
So far lemmas have seen minimal changes needed to adapt to Lean core
environment.
---------
Co-authored-by: Scott Morrison <scott.morrison@gmail.com>
This upstreams NatCast and IntCast alone independent of norm_cast in
#3322.
This will allow more efficiently upstreaming parts of Std.Data.Int
relevant for omega.
---------
Co-authored-by: Scott Morrison <scott.morrison@gmail.com>
By having the `pp.proofs` feature use `⋯` when omitting proofs, when
users copy/paste terms from the InfoView the elaborator can give an
error message explaining why the term cannot be elaborated.
Also adds `pp.proofs.threshold` option to allow users to pretty print
shallow proof terms. By default, only atomic proof terms are pretty
printed.
This adjustment was suggested in PR #3201, which added `⋯` and the
related `pp.deepTerms` option.
This will collect definitions from Std.Logic
---------
Co-authored-by: David Thrane Christiansen <david@davidchristiansen.dk>
Co-authored-by: Scott Morrison <scott.morrison@gmail.com>
We previously had the syntax for `change` and `change at`, but no
implementation.
This moves Kyle's implementation from Std.
This also changes the `changeLocalDecl` function to push nodes to the
infotree about FVar aliases.
---------
Co-authored-by: Leonardo de Moura <leomoura@amazon.com>
Co-authored-by: David Thrane Christiansen <david@davidchristiansen.dk>
This moves the `rcases` and `obtain` tactics from Std, and makes them
built-in tactics.
We will separately move the test cases from Std after #3297
(`guard_expr`).
---------
Co-authored-by: Leonardo de Moura <leomoura@amazon.com>
This is used in the "Try this:" widget machinery powering `simp?`.
There is a test file in Std, which I am not upstreaming at the same
time, as that relies on more code actions / #guard_msgs material. That
test file will still of course test things from Std, and later it can be
reunited with the code it is testing.
---------
Co-authored-by: Leonardo de Moura <leomoura@amazon.com>
The induction principle used by `induction` may have explicit parameters
that are
not motive, target or “real” alternatives (that have the `motive` as
conclusion), e.g. restrictions on the `motive` or other parameters.
Previously, `induction` would treat them as normal alternatives, and try
to re-introduce the automatically reverted hypotheses. But this only
works when the `motive` is actually the conclusion in the type of that
alternative.
We now pay attention to that, thread that information through, and only
revert when needed.
Fixes#3212.
