13 Zeilen
255 B
Haskell
13 Zeilen
255 B
Haskell
module Comonad where
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-------------------
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-- comonad class --
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-------------------
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class Functor w => Comonad w
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where
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(=>>) :: w a -> (w a -> b) -> w b
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extract :: w a -> a
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duplicate :: w a -> w (w a)
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x =>> f = fmap f (duplicate x)
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