[Haskell-beginners] Question on (x:xs) form
Christian Maeder
Christian.Maeder at dfki.de
Thu Jan 2 14:54:36 UTC 2014
Am 23.12.2013 15:57, schrieb Angus Comber:
> Why are the brackets required? And what do they signify?
>
> Eg reverse' x:xs = reverse' xs ++ [x] results in a parse error.
I just want to add that "prefix application"/juxtaposition binds
stronger than "infix application" and that therefore spaces should be
put around infix symbols (like ":") to stress this fact:
reverse x:xs
is the same as
reverse x : xs
and both are parsed as
(reverse x) : xs
which is different from
reverse (x : xs)
although "x:xs" almost looks like "(x:xs)"
Cheers Christian
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