G'day all.
Quoting Johannes Waldmann
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.
Err... no. The phrase "design patterns" is a shorthand for "vocabulary of engineering experience". Zippers, continuation passing style, Church encoding... these are not what FP "is", but they are specific techniques that engineers working in Haskell need to know to use the language effectively. You can think of design patterns as techniques that you need to overcome shortcomings in the language. That's why you need special techniques for, say, iterators in C++ or Java where in Haskell that comes more or less for free. But then, you need special techniques for mutable global state in Haskell, where in C++ or Java you get that for free. Or, to put it another way, nothing is ever free. There is no GoF-like book for Haskell because it's not an idea that needs promoting in printed form. We just point people to the wiki. Cheers, Andrew Bromage