2014-06-30 18:44:47 +00:00
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-- Copyright (c) 2014 Microsoft Corporation. All rights reserved.
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-- Released under Apache 2.0 license as described in the file LICENSE.
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-- Author: Leonardo de Moura
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2014-06-30 02:30:38 +00:00
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import logic
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inductive option (A : Type) : Type :=
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| none {} : option A
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| some : A → option A
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2014-07-29 02:58:57 +00:00
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theorem inhabited_option [instance] (A : Type) : inhabited (option A) :=
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inhabited_intro none
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