src/CCL/wfd.thy
author oheimb
Fri Jun 02 20:38:28 2000 +0200 (2000-06-02)
changeset 9028 8a1ec8f05f14
parent 289 78541329ff35
permissions -rw-r--r--
added HOL/Prolog
     1 (*  Title: 	CCL/wfd.thy
     2     ID:         $Id$
     3     Author: 	Martin Coen, Cambridge University Computer Laboratory
     4     Copyright   1993  University of Cambridge
     5 
     6 Well-founded relations in CCL.
     7 *)
     8 
     9 Wfd = Trancl + Type +
    10 
    11 consts
    12       (*** Predicates ***)
    13   Wfd        ::       "[i set] => o"
    14       (*** Relations ***)
    15   wf         ::       "[i set] => i set"
    16   wmap       ::       "[i=>i,i set] => i set"
    17   "**"       ::       "[i set,i set] => i set"      (infixl 70)
    18   NatPR      ::       "i set"
    19   ListPR     ::       "i set => i set"
    20 
    21 rules
    22 
    23   Wfd_def
    24   "Wfd(R) == ALL P.(ALL x.(ALL y.<y,x> : R --> y:P) --> x:P) --> (ALL a.a:P)"
    25 
    26   wf_def         "wf(R) == {x.x:R & Wfd(R)}"
    27 
    28   wmap_def       "wmap(f,R) == {p. EX x y. p=<x,y>  &  <f(x),f(y)> : R}"
    29   lex_def
    30   "ra**rb == {p. EX a a' b b'.p = <<a,b>,<a',b'>> & (<a,a'> : ra | (a=a' & <b,b'> : rb))}"
    31 
    32   NatPR_def      "NatPR == {p.EX x:Nat. p=<x,succ(x)>}"
    33   ListPR_def     "ListPR(A) == {p.EX h:A.EX t:List(A). p=<t,h$t>}"
    34 end