improved error output -- variant/mark bounds;
simplified infer_types -- always freeze, no result substitution;
(* Title: HOL/MetisExamples/ROOT.ML
ID: $Id$
Author: Lawrence C Paulson, Cambridge University Computer Laboratory
Testing the metis method.
*)
use_thys ["set", "BigO", "Abstraction", "BT", "Message", "Tarski", "TransClosure"];