On Thu, 7 Aug 2008, Sukit Tretriluxana wrote:
Dear Haskell experts,
I am currently studying Groovy language. An experiment I did with its closure is to perform closure/function "curry" using an array containing the values for the parameter binding. See the sample below.
int addThemUp(a,b,c,d,e) { a+b+c+d+e } def arrayCurry(arr, cls) { arr.inject(cls) { c, v -> c.curry(v) } } println addThemUp(1,2,3,4,5) println arrayCurry([1,2,3,4,5], this.&addThemUp)() println arrayCurry([1,2,3,4], this.&addThemUp)(5)
The printouts from the above code are the same, verifying that the code works fine. Then I come to ask myself how I can do the same in Haskell. I'm not a Haskell expert so I couldn't figure it. I wonder if you guys could shed some light on this.
I do not know Groovy, but maybe you want something like addThemUp :: Num a => (a,a,a,a,a) -> a addThemUp (a,b,c,d,e) = a+b+c+d+e -- should be better named list5Curry or so arrayCurry :: ((a,a,a,a,a) -> a) -> [a] -> a arrayCurry cls [a,b,c,d,e] = cls (a,b,c,d,e) print (addThemUp(1,2,3,4,5::Int)) print (arrayCurry addThemUp [1,2,3,4,5::Int]) However, it's hardly of any use, since you won't use a list if the number of elements is fixed (and small) or if the elements even must have distinct types.