PROPOSAL: Some more 'Applicative' combinators
apfelmus
apfelmus at quantentunnel.de
Wed Jan 9 05:22:37 EST 2008
Bryan O'Sullivan wrote:
> Why not make the task specificity clearer, with a separate
> Control.Applicative.Parsing module?
Iavor Diatchki wrote:
> What would be the benefit of having a separate module?
Well, putting those combinators in Control.Applicative would suggest
that applicative functors are for parsing only :)
> By the way, the combinators are all variations of 'many': 'skipMany'
> is just like 'many' but ignoring the results; 'endBy' performs a
> "cleanup" computation after each iteration; "sepBy" performs a
> "cleanup" operation between iterations. As I said before, these are
> just ordinary control structures.
What I want to say is that I doubt that many and friends are general
purpose. Is there an example of an applicative functor that is not a
parser but for which many , skipMany and so on make sense / are
useful? For [] and Maybe, both
many [1]
many $ Just 1
just give a stack overflow.
Regards,
apfelmus
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