[Haskell-cafe] First time haskell - parse error!
ketil at malde.org
Wed Mar 10 02:47:00 EST 2010
"S. Doaitse Swierstra" <doaitse at cs.uu.nl> writes:
>> then (s1 ++ s2 ++ s3 ++ s4) where
>> s1 = "Golds "
>> s2 = show (gold s g)
>> s3 = ", Silvers "
>> s4 = show (silver s g)
> If you want to keep the definitions local to the expression you should write
..but I think it is better style to avoid this kind of one-off named
values. I much prefer:
then "Golds "++show (gold s g)++...
For some reason, this is a style isse that doesn't get much attention,
at least not in the non-functional language tradition, where temporary
variables are scattered all over. So instead of doing:
let ns y = not (isSpace y)
f x = takeWhile ns x
in map f
We can use anonymous functions in place of the uninformatively named
map (\x -> takeWhile (\y -> not (isSpace y)) x)
and use partial application toward point-free-ness:
map (takeWhile (not . isSpace))
which IMO is a lot easier to read, taking up less screen and mind estate.
Of course it's possible to overdo the point-free thing (commonly
referred to as "pointless"), but I think it's great when you can
eliminate gratuitous naming like this.
If I haven't seen further, it is by standing in the footprints of giants
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