Gfp.thy
author nipkow
Fri, 02 Dec 1994 11:43:20 +0100
changeset 194 b93cc55cb7ab
parent 178 12dd5d2e266b
permissions -rw-r--r--
small updates because datatype list is now used. In particular Nil -> []

(*  Title: 	HOL/gfp.thy
    ID:         $Id$
    Author: 	Lawrence C Paulson, Cambridge University Computer Laboratory
    Copyright   1994  University of Cambridge

Greatest fixed points (requires Lfp too!)
*)

Gfp = Lfp +
consts gfp :: "['a set=>'a set] => 'a set"
defs
 (*greatest fixed point*)
 gfp_def "gfp(f) == Union({u. u <= f(u)})"
end