32 lines
561 B
Text
32 lines
561 B
Text
/-
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Copyright (c) 2017 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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Authors: Sebastian Ullrich
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The identity Monad.
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-/
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prelude
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import Init.Core
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universe u
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def Id (type : Type u) : Type u := type
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namespace Id
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@[always_inline]
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instance : Monad Id where
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pure x := x
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bind x f := f x
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map f x := f x
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def hasBind : Bind Id :=
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inferInstance
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@[always_inline, inline]
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protected def run (x : Id α) : α := x
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instance [OfNat α n] : OfNat (Id α) n :=
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inferInstanceAs (OfNat α n)
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end Id
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