haskell - Difference in <$> and fmap -

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i have line of code:

(++) <$> "hallo" <*> "du"

which outputs just "hallodu"

in "learn haskell great good" learned <$> , fmap same , indeed ghci outputs same type signature me. nevertheless, when write: 

fmap (++) "hallo" <*> "du"

where difference?

yes <$> , fmap same thing using them in different expressions.

(++) <$> "hallo" <*> "du"

is equivalent to:

(++) `fmap` "hallo" <*> "du"

moving fmap in infix position yields:

fmap (++) (just "hallo") <*> "du"

this due operator precedence , why <$> more readable of time.

note in expression:

fmap (++) "hallo" <*> "du"

you passing 3 arguments fmap ((++), just , "hallo"), type doesn't match <*> wants.

you want pass 2 arguments: (++) , just "hallo".


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