18 lines
459 B
Text
18 lines
459 B
Text
-- 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: Jeremy Avigad, Floris van Doorn
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-- Empty type
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-- ----------
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import logic.cast
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inductive empty : Type
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namespace empty
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protected theorem elim (A : Type) (H : empty) : A :=
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rec (λe, A) H
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protected theorem subsingleton [instance] : subsingleton empty :=
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subsingleton.intro (λ a b, !elim a)
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end empty
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