[Haskell-cafe] Pointed, but not Applicative

Sebastian Fischer fischer at nii.ac.jp
Mon Aug 29 06:47:22 CEST 2011


On Mon, Aug 29, 2011 at 12:24 PM, Maciej Marcin Piechotka
<uzytkownik2 at gmail.com> wrote:

> instance Functor FList where
>    f `fmap` FList g = ...?

Yes, Functor is also one of the classes that can only be implemented
by converting to ordinary lists (I think).

So FList could only be made an instance of Pointed without (certain)
superclass constraints.

Sebastian



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