Evan Laforge wrote:
>> splitBy :: (a -> Bool) -- ^ whether element is a seperator
>>         -> [a] -- ^ list to split
>>         -> [[a]]

P.S. inspecting more than one element looks like an over-generalization
to me and should be left to parsers or regexp libs.


It's more generally useful if you don't drop the separators from the output:

splitSepWith f = map (dropWhile f) . splitWith f
spaces = splitSepWith Char.isSpace

But this still won't let you split on comma and spaces.  Either
regexes, or pass in a [tok] -> ([conumed], [rest]) type parser:

splitWith :: ([a] -> ([a], [a])) -> [a] -> [[a]]

... but why not make it take parsec parsers and put it in a parsec
util module or something (if it isn't already there!):

splitWith (Parsec.char ',' >> Parsec.spaces)

... of course, then you might ask why not use Parsec.sepBy :) but
maybe the "split on elt" concept is easier to learn than "write a
whole parser".

I guess the problem with the splitWith thing is that it's a slippery
path that leads right up to full-on parsers.

Exactly, and this is why we didn't reach a concensus last time.

Would someone like to make a concrete proposal (with code!) for 2-3 functions we could reasonably add to Data.List?

Cheers,
        Simon
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