(* Check pattern-unification on evars in apply unification *)

Axiom copyf_atom : forall tau:Type, forall t t':tau, copyf tau t t' -> eq tau t t'.
Axiom copyf_fun: forall tau tau':Type, forall t t':(tau->tau'),
copyr (tau->tau') t t'
->(forall x y:tau, forall z1 z2:tau',
(copy tau x y)->
(subst tau tau' t x z1)->
(subst tau tau' t' y z2)->
copyf tau' z1 z2).