maybeRead in base

Twan van Laarhoven twanvl at
Thu Aug 16 13:16:46 CEST 2012

On 15/08/12 19:02, Edward Kmett wrote:
> I'm not a huge fan of (.:), but you insist on adding it, please generalize it to
> fmap.fmap.
> (.:) :: (Functor f, Functor g) => (a -> b) -> f (g a) -> f (g b)
> This subsumes the other use case.

For the love of Categories, please don't go down this road. fmap is not the 
proper generalization of (.).


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