Function overloading

function_overload.js

test = require("tape");

function addMethod(object, name, fn){
  object._store = object._store || {};
  object._store[name] = object._store[name] || {};
  object._store[name][fn.length] = fn;
  object[name] = function() {
    if(this._store[name][arguments.length])
      return this._store[name][arguments.length].apply(this, arguments);
  };
}

test("function overload", function(t){
  var test_obj = {};
  function add2(a,b) { return a+b };
  function add3(a,b,c) { return a + b + c;}
  addMethod(test_obj, "add", add2);
  addMethod(test_obj, "add", add3);
  
  t.equal(test_obj.add(1,2), 3, "add with 2 parameters");
  t.equal(test_obj.add(1,2,3), 6, "add with 3 parameters");
  t.end();
})