[Haskell-cafe] Data.Tree.Zipper in the standard libraries

Luke Palmer lrpalmer at gmail.com
Fri May 23 13:34:50 EDT 2008

On Fri, May 23, 2008 at 10:55 AM, Jules Bean <jules at jellybean.co.uk> wrote:
> Krasimir Angelov wrote:
>> The monads design is used in Data.Map i.e.
>> lookup :: (Monad m, Ord k) => k -> Map k a -> m a
> which is widely considered a poor design decision and a wart on Data.Map.

It is?  Can you point to somewhere explaining that?  I rather liked that idiom.


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