On 22/09/2010 10:20 AM, Johannes Waldmann wrote:
- are there any prior art in documenting idioms and patterns in FP [...] you got this backwards: what some folks call "idioms and (design) patterns" actually *is* FP, because it is just this: higher order functions. And it's been there some decades (lambda calculus). That also explains the absence of any Design Patterns/Gang-of-Four kind of book for Haskell - it's just not needed. (as you say, map and fold are your patterns.)
Or rather, in Haskell your design patterns are things like "accumulating parameters", "difference lists", "finally tagless", "combinator libraries" and the like. Sadly, in Haskell at least, most of these things are a kind of "oral tradition" which isn't actually written down anywhere. (Which means that basically the only way to learn Haskell is to hang around and ask lots of dumb questions and gradually learn by osmosis...)