Now, only `(<- ...)`s occurring in the condition of a pure if-then-else
are lifted.
That is, `if (<- foo) then ... else ...` is ok, but `if ... then (<-
foo) else ...` is not. See #3713closes#3713
This PR also adjusts this repo. Note that some of the `(<- ...)` were
harmless since they were just accessing some
read-only state.
I think this was in error in my original Mathlib implementation. We're
not interested in relations other than `=`, so there is no point uses
`MVarId.applyRfl`, which just looks up `@[refl]` tagged lemmas and tries
those.
In a separate PR, I will change `MVarId.applyRfl` so it has a flag to
control whether on `=` it should just hand-off to `MVarId.refl`, or
fail. Failure is appropriate in the version we call from the `rfl`
macro, to avoid doing a double `IsDefEq` check on every `rfl`!
This makes several changes to rw? and lazy discrimination trees based on
test failures in rewrite search.
Changes include:
1. Reverting to Mathlib function for candidate lemma priority in rw?
2. Introducing additional filters for auto-generated named in lazy
discriminator tree.
3. Refactoring lazy discriminator values to clarify what is stored.
4. Including star keys in calculation of match closeness in
prioritization.
5. Using more fields in current core context when initializing lazy
discriminator tree and avoiding max heartbeat issues.
---------
Co-authored-by: Scott Morrison <scott.morrison@gmail.com>
This updates the rw? tactic from Mathlib to use lazy discriminator trees
and upstreams it.
---------
Co-authored-by: Scott Morrison <scott.morrison@gmail.com>
