On Sat, Nov 21, 2009 at 05:43:29PM -0500, Isaac Dupree wrote:
why has no one mentioned: you most likely don't need to understand Arrows? I'm pretty good with Haskell, and Arrows are still somewhat confusing to me. Why? Most problems I've worked with in Haskell have had more-idiomatic solutions than Arrows. (examples include: Monad; Functor; Applicative; just plain functions; plain old lack of type-class abstraction.) It's not so easy or useful to understand any abstraction/class without using at least two or three useful examples/instances of it first.
In defence of my solution, I haven't really used the power of the arrows. The "problem" is that the quite useful functions first, second, (***) and (&&&) are defined within Control.Arrow. Cheers, :) -- Felipe.