Literals aren't sorted any more. Output overloaded constants' type var instantiations.
%ID: $Id$
%Author: Jia Meng, NICTA
%extensionality for const-types-only
clause(
forall([A, B, F, G],
or( not(equal(hAPP(F,hAPP(hAPP(hEXTENT(A,B),F),G)),hAPP(G,hAPP(hAPP(hEXTENT(A,B),F),G)))),
equal(F,G))),
a18 ).