[Haskell-beginners] Parametrizing [] as an instance of the Functor type class

Olumide 50295 at web.de
Thu Dec 31 13:06:18 UTC 2015


According to LYH, the list is an instance of the Functor type class:

instance Functor [] where
     fmap = map

Why does 'f' not appear in this expression?, considering that Functor is 
defined as

class Functor f where
     fmap :: (a -> b) -> f a -> f b

Overall, I'm a bit confused about the relationship between the type 
constructor f and [].

Thanks,

- Olumide



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