JavaScript Currying.

Curry.js

/*
	* Curried code to add multiple numbers
	
	Author : Jaseem Abid <[email protected]>
	
	* sum() expects 2 numbers are arguments
	* If 2 args are provided, it returns sum as usual.
	* If one arg is provided, it returns a
	function which expects one more arg. JS closures can
	'remember the first argument' and work accordingly.
	* If no arguments are supplied, it returns itself.
*/

sum = function sum(a,b) {
	if (arguments.length < 1) {
		return sum;
	} else if (arguments.length < 2) {
		return function(c) {
			return c + a;
		}
	} else return a+b;
};

/* 
	All calls give the same expected result, 5
*/

console.log( sum(2,3) );
console.log( sum(2)(3) );
console.log( sum()()(2)(3) );