Library Coq.Classes.Init

Initialization code for typeclasses, setting up the default tactic

for instance search.
Author: Matthieu Sozeau Institution: LRI, CNRS UMR 8623 - University Paris Sud
Hints for the proof search: these combinators should be considered rigid.

Require Import Coq.Program.Basics.

Apply using the same opacity information as typeclass proof search.

Ltac class_apply c := autoapply c with typeclass_instances.

The unconvertible typeclass, to test that two objects of the same type are actually different.
Class Unconvertible (A : Type) (a b : A) := unconvertible : unit.

Ltac unconvertible :=
  match goal with
    | |- @Unconvertible _ ?x ?y => unify x y with typeclass_instances ; fail 1 "Convertible"
    | |- _ => exact tt

Hint Extern 0 (@Unconvertible _ _ _) => unconvertible : typeclass_instances.