| author | clasohm |
| Tue, 09 Nov 1993 13:30:13 +0100 | |
| changeset 15 | 25ec61ee621c |
| parent 0 | 7949f97df77a |
| permissions | -rw-r--r-- |
| 0 | 1 |
(* Title: HOL/lfp.thy |
2 |
ID: $Id$ |
|
3 |
Author: Lawrence C Paulson, Cambridge University Computer Laboratory |
|
4 |
Copyright 1992 University of Cambridge |
|
5 |
||
6 |
The Knaster-Tarski Theorem |
|
7 |
*) |
|
8 |
||
9 |
Lfp = Sum + |
|
10 |
consts lfp :: "['a set=>'a set] => 'a set" |
|
11 |
rules |
|
12 |
(*least fixed point*) |
|
13 |
lfp_def "lfp(f) == Inter({u. f(u) <= u})"
|
|
14 |
end |