On 04/07/10 09:58, Felipe Lessa wrote:
<$$> will be as concise and useful as<$>, maybe even more, because `flip fmap` isn't valid.
This is the annoying part. Aw, Haskell! I suppose we could name the combinator `flipfmap`... and it would be clear what it meant... I disagree with the consistency argument. I don't think <*> -> <**> is a very good precedent. It has confused me. Far more people are familiar with functor than applicative (so this precedent would be applied mostly to an audience who's unfamiliar with it). >>= -> =<< , although perhaps silly, at least looks enough like a mirrored version that you can guess... I'd say "let's fix the fixity of fmap!" except we can't because Prelude exports it. Besides, IMHO fixity isn't too big a deal, because one can use parentheses and they're rather less confusing to read than things being in the "wrong" order or expressions using symbol-operators that the reader doesn't know. I've used `fmap`, infix like that, sometimes... although more recently I've come to think that it's not necessary to use infix operators at all for clarity. A thought: for
do m1 m2 m3 <$$> bigPieceOfCodeThatVisuallyBreaks theSequentialNatureOfADoExpression how about using do m1 m2 flip fmap m3 $ bigPieceOfCodeThatVisuallyBreaks theSequentialNatureOfADoExpression ? (not sure though.. I like using "forM_" more than "flip mapM_"..)
-Isaac