I was looking at the Applicative
class within Haskell libraries and stumbled across Alternative
.
What is this class good for? A google search did not reveal anything particularly insightful. And it seems to be completely out of place, bundled as it is with the Applicative package.
Could someone please post a possible scenario where you would use this class?
It's commonly used with parser combinators. For example, if space
is a parser combinator that matches a single whitespace character, many space
would be one that would match consecutive whitespace.
I can agree that it's slightly out of place in Control.Applicative
, though.