Parameter empty: t.

(* Specifications: *)
Axiom repr_empty:
forall a, repr empty a = a.
Axiom sameclass_empty:
forall a b, sameclass empty a b -> a = b.
Axiom repr_empty:
forall a, repr empty a = a.
Axiom sameclass_empty:
forall a b, sameclass empty a b -> a = b.