Re: [Haskell-cafe] Cal, Clojure, Groovy, Haskell, OCaml, etc.

On Wed, Sep 30, 2009 at 6:45 PM, namekuseijin wrote:

On Mon, Sep 28, 2009 at 11:50 PM, Hong Yang wrote:

...

learn and use. In my humble opinion, Haskell has a lot of libraries, but most of them offer few examples of how to use the modules. In this regards, Perl is much much better.

The Perl call is spot on. Specially because Haskell has been incorporating so much syntatic sugar that it's almost looking Perlish noise already:

import Data.Array.Diff import Data.IArray

update :: (Char -> [Int]) -> DiffArray Int ModP -> Char -> DiffArray Int ModP update lookup arr c = arr // (map calc . lookup $ c) where calc i = (i, (arr ! i) + (arr ! (i-1)))

solve line sol = (foldl' (update lookup) iArray line) ! snd (bounds iArray) where iArray = listArray (0, length sol) $ 1 : map (const 0) sol lookup c = map (+1) . findIndices (== c) $ sol

I've not been following Haskell too much and am completely lost when reading code like that. I understand (+1), : and ! but what the hell are . and $ for? And that weird monad symbol in the Haskell logo is not even used! >>= Not quite the worst example of such line noise much of Haskell idiomatic code uses nowadays, though.

Point is: >>= . $ : ! `` and meaningful whitespace are all nice shortcuts, but also hairy confusing...

I overall agree with the sentiment (I avoid declaring operators at all costs), but the example is a bad one. $, ., and >>= are all very basic to Haskell, and should be picked up almost immediately. As far as becoming line noise like Perl, well, I happen to like Perl :). Michael