Generalize StringLike?

[safareli]

Currently StringLike is implemented by String and looks like it was in mind to only allowe structures which contain some Chars.

But I think it could be easily changed to support arbitrary containers of arbitrary data.
for example one might define some sumtype Data Color = Red | Blue| Orange ... and have wants to parse List Color into some other structure or maybe even in itself and just validate that colors in the List are in correct order or whatever.

But the StringLike is limiting this kind of use.
What i think is that the class could be changed to:

class StringLike f where
  drop :: forall a. Int -> f a -> f a
  indexOf :: forall a. f a -> f a -> Maybe Int
  null :: forall a. f a -> Boolean
  uncons :: forall a.  f a -> Maybe { head :: a, tail :: f a }

This way one could implement StringLike for List/Array ... and for example anyChar will change to

anyChar :: forall f s m. StringLike f => Monad m => ParserT (f s) m s

[paf31]

I'm not sure I like the type of indexOf there. I'd rather use a fundep for the String -> Char dependency, and break indexOf out into its own class if need be.

[safareli]

what about uncons? Char is hardcoded in head

[jamesdbrock]

Deleted the StringLike class in v7.0.0.