src/HOL/Option.thy
author nipkow
Tue Apr 08 10:48:42 1997 +0200 (1997-04-08)
changeset 2919 953a47dc0519
parent 2019 b45d9f2042e0
child 4133 0a08c2b9b1ed
permissions -rw-r--r--
Dep. on Provers/nat_transitive
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(*  Title:      Option.thy
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    ID:         $Id$
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    Author:     Tobias Nipkow
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    Copyright   1994  TU Muenchen
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Datatype 'a option
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*)
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Option = Arith +
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datatype 'a option = None | Some 'a
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end