Difference between revisions of "Functor"
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BrettGiles (talk | contribs) m (Adding Monad category) |
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fmap (p . q) = (fmap p) . (fmap q) |
fmap (p . q) = (fmap p) . (fmap q) |
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− | [[Category:Standard classes]] |
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[[Category:Monad]] |
[[Category:Monad]] |
Revision as of 02:34, 31 July 2008
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)