23 lines
703 B
Text
23 lines
703 B
Text
/-
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Copyright (c) 2016 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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-/
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prelude
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import init.monad init.alternative
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open list
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inline definition list_fmap {A B : Type} (f : A → B) (l : list A) : list B :=
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map f l
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inline definition list_bind {A B : Type} (a : list A) (b : A → list B) : list B :=
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join (map b a)
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inline definition list_return {A : Type} (a : A) : list A :=
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[a]
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definition list_is_monad [instance] : monad list :=
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monad.mk @list_fmap @list_return @list_bind
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definition list_is_alternative [instance] : alternative list :=
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alternative.mk @list_fmap @list_return (@fapp _ _) @nil @list.append
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