haskell - Fmap and map, I can't see the difference -

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i'm trying understand functors are, far can't. what's difference between these 2:

prelude> fmap (+1) [1..9] [2,3,4,5,6,7,8,9,10]  prelude> map (+1) [1..9] [2,3,4,5,6,7,8,9,10]

for lists, there no difference, map fmap specialised lists.

fmap has more general type:

fmap :: functor f => (a -> b) -> f -> f b

this means can used functor e.g.

fmap (+ 3) (just 4)          -- 7 fmap (+ 4) (+ 3) 1           -- 8. functions functors fmap = (.) fmap read getline :: io int  -- io functor

while map has type

map :: (a -> b) -> [a] -> [b]

if @ source, functor instance lists defines fmap map:

instance functor []     fmap = map

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