src/ZF/Epsilon.thy
author clasohm
Tue Feb 06 12:27:17 1996 +0100 (1996-02-06)
changeset 1478 2b8c2a7547ab
parent 1401 0c439768f45c
child 2469 b50b8c0eec01
permissions -rw-r--r--
expanded tabs
     1 (*  Title:      ZF/epsilon.thy
     2     ID:         $Id$
     3     Author:     Lawrence C Paulson, Cambridge University Computer Laboratory
     4     Copyright   1993  University of Cambridge
     5 
     6 Epsilon induction and recursion
     7 *)
     8 
     9 Epsilon = Nat + "mono" +
    10 consts
    11     eclose,rank ::      i=>i
    12     transrec    ::      [i, [i,i]=>i] =>i
    13 
    14 defs
    15   eclose_def    "eclose(A) == UN n:nat. nat_rec(n, A, %m r. Union(r))"
    16   transrec_def  "transrec(a,H) == wfrec(Memrel(eclose({a})), a, H)"
    17   rank_def      "rank(a) == transrec(a, %x f. UN y:x. succ(f`y))"
    18 end