src/ZF/Epsilon.thy
changeset 0 a5a9c433f639
child 124 858ab9a9b047
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/ZF/Epsilon.thy	Thu Sep 16 12:20:38 1993 +0200
     1.3 @@ -0,0 +1,18 @@
     1.4 +(*  Title: 	ZF/epsilon.thy
     1.5 +    ID:         $Id$
     1.6 +    Author: 	Lawrence C Paulson, Cambridge University Computer Laboratory
     1.7 +    Copyright   1993  University of Cambridge
     1.8 +
     1.9 +Epsilon induction and recursion
    1.10 +*)
    1.11 +
    1.12 +Epsilon = Nat +
    1.13 +consts
    1.14 +    eclose,rank ::      "i=>i"
    1.15 +    transrec    ::      "[i, [i,i]=>i] =>i"
    1.16 +
    1.17 +rules
    1.18 +  eclose_def	"eclose(A) == UN n:nat. nat_rec(n, A, %m r. Union(r))"
    1.19 +  transrec_def	"transrec(a,H) == wfrec(Memrel(eclose({a})), a, H)"
    1.20 +  rank_def    	"rank(a) == transrec(a, %x f. UN y:x. succ(f`y))"
    1.21 +end