lean4-htt/tests/lean/run/unfold_issue.lean
2017-01-17 15:50:54 -08:00

13 lines
303 B
Text

def f : nat → nat → nat
| 0 := λ x, x
| (n+1) := λ x, x + 1
meta def check_expr (p : pexpr) (t : expr) : tactic unit :=
do e ← tactic.to_expr p, guard (t = e)
example (n : nat): f (n+1) n = n + 1 :=
begin
unfold f,
(tactic.target >>= check_expr `((n + 1 = n + 1))),
reflexivity,
end