curry.js

Function.prototype.curry = function(){
  var slice = Array.prototype.slice,
    args = slice.apply(arguments),
    that = this

  return function(){
    var aa = args.concat(slice.apply(arguments))
    if(that.arity == aa.length)
      return that.apply(null, aa)
    else
      return Function.prototype.curry.apply(that, aa)
  }
}

g = function(a, b, c){ print(a, b, c) }
f = g.curry()
f(1)(2)(3)
f(1,2)(3)
f(1)(2,3)