lean4-htt/src/Init/Control/Id.lean
2020-12-12 10:36:26 -08:00

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/-
Copyright (c) 2017 Microsoft Corporation. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Authors: Sebastian Ullrich
The identity Monad.
-/
prelude
import Init.Core
universe u
def Id (type : Type u) : Type u := type
namespace Id
instance : Monad Id where
pure x := x
bind x f := f x
map f x := f x
@[inline] protected def run (x : Id α) : α := x
instance [OfNat α n] : OfNat (Id α) n :=
inferInstanceAs (OfNat α n)
end Id