Functor: Difference between revisions
No edit summary |
mNo edit summary |
||
| Line 1: | Line 1: | ||
{{Standard class|Functor|module=Control.Monad|package=base}} | {{Standard class|Functor|module=Control.Monad|module=doc=Control-Monad|package=base}} | ||
The '''Functor''' class is defined like this: | The '''Functor''' class is defined like this: | ||
Revision as of 03:20, 2 January 2006
| import doc=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)