13 lines
311 B
Text
13 lines
311 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 `((λ x, x + 1) n = n + 1)),
|
|
reflexivity,
|
|
end
|