Currying (ML)

	(* old way to get the effect of multiple arguments *)
	fun sorted3_tupled (x,y,z) = z >= y andalso y >= x
	val t1 = sorted3_tupled (7,9,11)
	(* new way using currying *)
	val sorted3 = fn x => fn y => fn z => z >= y andalso y >= x
	val t2 = ((sorted3 7) 9) 11
	(* we can curry using syntactic sugar *)
	val t3 = sorted3 7 9 11
	(* declare a curried function by using spaces between multi arguments *)
	fun sorted3_nicer x y z = z >= y andalso y >= x
	(* now we can write a fold function using currying *)
	fun fold f acc xs = (* means fun fold f = fn acc => fn xs => *)
	case xs of
	[] => acc
	|x:xs' => fold f (f(acc,x)) xs'
	fun sum xs = fold (fn (x,y) => x + y) 0 xs

view raw gistfile1.sml hosted with ❤ by GitHub