added parse_document (optional unchecked header material);
parse: parse_document instead of parse_element;
(* 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"];