lean4-htt/tests/lean/run/grind_match1.lean
Leonardo de Moura 00ef231a6e
feat: split on match-expressions in the grind tactic (#6569)
This PR adds support for case splitting on `match`-expressions in
`grind`.
We still need to add support for resolving the antecedents of
`match`-conditional equations.
2025-01-08 03:10:11 +00:00

67 lines
1.5 KiB
Text
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

def g (xs : List α) (ys : List α) :=
match xs, ys with
| [], _ => ys
| _::_::_, [ ] => []
| x::xs, ys => x :: g xs ys
attribute [simp] g
set_option trace.grind.assert true
set_option trace.grind.split.candidate true
set_option trace.grind.split.resolved true
/--
info: [grind.assert] (match as, bs with
| [], x => bs
| head :: head_1 :: tail, [] => []
| x :: xs, ys => x :: g xs ys) =
d
[grind.split.candidate] match as, bs with
| [], x => bs
| head :: head_1 :: tail, [] => []
| x :: xs, ys => x :: g xs ys
[grind.assert] bs = []
[grind.assert] a₁ :: f 0 = as
[grind.assert] f 0 = a₂ :: f 1
[grind.assert] ¬d = []
[grind.assert] Lean.Grind.EqMatch
(match a₁ :: a₂ :: f 1, [] with
| [], x => bs
| head :: head_1 :: tail, [] => []
| x :: xs, ys => x :: g xs ys)
[]
[grind.split.resolved] match as, bs with
| [], x => bs
| head :: head_1 :: tail, [] => []
| x :: xs, ys => x :: g xs ys
-/
#guard_msgs (info) in
example (f : Nat → List Nat) : g as bs = d → bs = [] → a₁ :: f 0 = as → f 0 = a₂ :: f 1 → d = [] := by
unfold g
grind
example : g as bs = d → as = [] → d = bs := by
unfold g
grind
def f (x : List α) : Bool :=
match x with
| [] => true
| _::_ => false
example : f a = b → a = [] → b = true := by
unfold f
grind
def f' (x : List Nat) : Bool :=
match x with
| [] => true
| _::_ => false
attribute [simp] f'
#check f'.match_1.eq_1
example : f' a = b → a = [] → b = true := by
unfold f'
grind