blob: ff4509c4a8e34279c333cf166f17f8736c1c1603 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
|
Class by_transparent_abstract {T} (x : T) := make_by_transparent_abstract : T.
Hint Extern 0 (@by_transparent_abstract ?T ?x) => change T; transparent_abstract exact_no_check x : typeclass_instances.
Goal True /\ True.
Proof.
split.
transparent_abstract exact I using foo.
let x := (eval hnf in foo) in constr_eq x I.
let x := constr:(ltac:(constructor) : True) in
let T := type of x in
let x := constr:(_ : by_transparent_abstract x) in
let x := (eval cbv delta [by_transparent_abstract] in (let y : T := x in y)) in
pose x as x'.
simpl in x'.
let v := eval cbv [x'] in x' in tryif constr_eq v I then fail 0 else idtac.
hnf in x'.
let v := eval cbv [x'] in x' in tryif constr_eq v I then idtac else fail 0.
exact x'.
Defined.
Check eq_refl : I = foo.
Eval compute in foo.
|
