On 17/08/13 10:11, Christopher Done wrote: > Anyone ever needed this? Me and John Wiegley were discussing a decent > name for it, John suggested inv as in involution. E.g. First thing I thought was ‘inverse’… > > inv reverse (take 10) > inv reverse (dropWhile isDigit) > trim = inv reverse (dropWhile isSpace) . dropWhile isSpace > > That seems to be the only use-case I've ever come across. > I do this a lot as well. Why not skip the ‘g’ all together and have ‘f . reverse . f’ if that's all we're doing? You could even call it fromEnd at that point and we end up with a rather intuitive ‘fromEnd (drop 10)’. Maybe even just have an operator. > There's also this one: > > co f g = f g . g > > which means you can write > > trim = co (inv reverse) (dropWhile isSpace) > > but that's optimizing an ever rarer use-case. >
Is this a proposal for addition to something or is it just general discussion? -- Mateusz K.
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Description: application/pgp-keys
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