Functor
From HaskellWiki
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fmap (p . q) = (fmap p) . (fmap q) | fmap (p . q) = (fmap p) . (fmap q) | ||
| - | [[Category: | + | |
| + | == More reading == | ||
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| + | * [http://www.haskellforall.com/2012/09/the-functor-design-pattern.html The functor design pattern] | ||
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| + | [[Category:Functor|*]] | ||
Current revision
| import Control.Monad |
The Functor class is defined like this:
class Functor f where fmap :: (a -> b) -> f a -> f b
All instances of Functor should obey:
fmap id = id fmap (p . q) = (fmap p) . (fmap q)
