gistfile1.txt

var Promise = require('bluebird');

Promise.extend = function(method, fn) {
    var Promise = this;
    Promise.prototype[method] = function Promise$_Proxy() {
        var $_len = arguments.length;
        var args = new Array($_len + 1); for(var $_i = 0; $_i < $_len; ++$_i) {args[$_i + 1] = arguments[$_i];}
        var bound = this._isBound() ? this._boundTo : null;
        
        return this._then(function(obj) {
                args[0] = obj;
                return fn.apply(bound, args);
            },
            void 0,
            void 0,
            void 0,
            void 0,
            this[method]
       );
    };
};

Promise.extend('hello', function (res, bar) {
    console.log('resolved value: ', res);
    console.log('passed argument: ', bar);
    return this.hello();
});

function Foo() {
  this.deferred = Promise.defer();
}
Foo.prototype.hello = function (res) {
  console.log('called method on bound object:', res);
  return this.deferred.promise;
};
Foo.prototype.resolve = function (val) {
  this.deferred.resolve(val);
};

var newFoo = new Foo();
Promise.bind(newFoo).return('hi').hello('bar').then(function (res) {
  this.hello(res);
});
newFoo.resolve('keke');
Promise.resolve('hi').hello('bar'); // throws