IOA/meta_theory/Option.thy
author nipkow
Wed, 09 Nov 1994 19:51:09 +0100
changeset 168 44ff2275d44f
parent 156 fd1be45b64bf
permissions -rw-r--r--
Added headers and made various small mods.

(*  Title:      Option.thy
    ID:         $Id$
    Author:     Tobias Nipkow
    Copyright   1994  TU Muenchen

Datatype 'a option
*)

Option = Arith +
datatype 'a option = None | Some('a)
end