# 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.
Typeclasses Opaque id const flip compose arrow impl iff not all.
Apply using the same opacity information as typeclass proof search.
Ltac class_apply c := autoapply c using 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
end.
Hint Extern 0 (@Unconvertible _ _ _) => unconvertible : typeclass_instances.