Zulip Chat Archive

Stream: lean4

Topic: apply? using tombstones


Michael Stoll (Nov 17 2024 at 20:55):

I noticed recently (but can't tell exactly when) that the suggestions apply? produces frequently contain names with tombstone; e.g.

example (a b : Nat) : a - b = 0 := by
  -- First suggestion is "Try this: refine Eq.symm (Nat.eq_of_beq_eq_true ?a✝)"
  apply?

(There are more suggestions, and not all of them have tombstones.)

This is annoying, as clicking on the suggestion gives you an error, and you have to remove the to make it work.

Joachim Breitner (Nov 17 2024 at 22:12):

It’s a known issue, but there isn’t really a good way to fix that. I guess understanding how to make inaccessible parameters accessible is something that for now we have to expert the user to do.

Kyle Miller (Nov 17 2024 at 22:24):

It could set pp.mvars to false before pretty printing. I don't expect mvar names to be useful in the apply? output.

Joachim Breitner (Nov 17 2024 at 22:47):

Oh, it's an mvar, not a daggered hypothesis here. Sorry for not reading carefully

Kim Morrison (Nov 18 2024 at 00:13):

lean#6108


Last updated: May 02 2025 at 03:31 UTC