src/CCL/lfp.thy
author berghofe
Mon, 21 Oct 2002 17:16:24 +0200
changeset 13667 0009325e9af0
parent 0 a5a9c433f639
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Replaced variantlist (quadratic) by gen_names (linear).
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(*  Title: 	HOL/lfp.thy
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    ID:         $Id$
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    Author: 	Lawrence C Paulson, Cambridge University Computer Laboratory
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    Copyright   1992  University of Cambridge
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The Knaster-Tarski Theorem
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*)
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Lfp = Set +
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consts lfp :: "['a set=>'a set] => 'a set"
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rules
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 (*least fixed point*)
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 lfp_def "lfp(f) == Inter({u. f(u) <= u})"
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end