758a17ab23
The unit datatype is used by automation. We want to be able to access its declaration without having to access all dependencies (e.g., decidable, subsingleton, inhabited, ...). This is *not* an optimization, but a way to make sure we can "import" unit before we import other declarations.
16 lines
582 B
Text
16 lines
582 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: Leonardo de Moura
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import data.unit.decl data.unit.thms logic.decidable logic.inhabited
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open decidable
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namespace unit
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protected theorem subsingleton [instance] : subsingleton unit :=
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subsingleton.intro (λ a b, equal a b)
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protected definition is_inhabited [instance] : inhabited unit :=
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inhabited.mk ⋆
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protected definition has_decidable_eq [instance] : decidable_eq unit :=
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take (a b : unit), inl (equal a b)
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end unit
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