[Haskell-beginners] f . g or f g or f $ g?
poczta at emanuelkoczwara.pl
Fri Feb 1 20:53:33 CET 2013
> Hello all
> I frequently get confused over f . g vs f g. I do understand the following
> g :: a->b
> f :: b ->c
> f.g :: a->c
> f g
> is a type error, because then f would have to accept a function (a->b) as its
> first parameter, but it only accepts a b.
> Is there a way to easily remember when to use f.g and when to use f g without
> having to do this type algebra.
Function composition is different than function application. Are you
mixing these concepts?
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