lean4-htt/library/init/functor.lean
2016-09-24 16:38:39 -07:00

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/-
Copyright (c) Luke Nelson and Jared Roesch. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Authors: Luke Nelson and Jared Roesch
-/
prelude
universe variables u v
class functor (F : Type u → Type v) : Type (max u+1 v) :=
(map : Π {A B : Type u}, (A → B) → F A → F B)
@[inline] definition fmap {F : Type u → Type v} [functor F] {A B : Type u} : (A → B) → F A → F B :=
functor.map
infixr ` <$> `:100 := fmap