[Haskell-cafe] Point-free style

Ketil Malde ketil+haskell at ii.uib.no
Fri Feb 11 03:00:48 EST 2005

Matthew Roberts <mattr at ics.mq.edu.au> writes:

>> [Point-free] compositions of functions with arity greater than 1,
>> [...] compositions of sections of composition or application,
>> arrow notation without the sugar, and so forth---will always be more
>> difficult to read and understand than the direct version.

> I have to agree (although I suspect few others will :))

I tend to agree, also.  Type signatures help, of course.  E.g. with
the previously mentioned and rather cryptic function

        (.) . (.) .(.)

I entered it into GHCi, and got

        :: forall a a b c a.
              (b -> c) -> (a -> a -> a -> b) -> a -> a -> a -> c

and it suddenly is much clearer what it does.

If I haven't seen further, it is by standing in the footprints of giants

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