Obejct.Create实现

实现原理

if (typeof Object.create !== "function") {
  Object.create = function (prototype, properties) {
    if (typeof prototype !== "object") { throw TypeError(); }
    function Ctor() {}
    Ctor.prototype = prototype;
    var o = new Ctor();
    if (prototype) { o.constructor = Ctor; }
    if (properties !== undefined) {
      if (properties !== Object(properties)) { throw TypeError(); }
      Object.defineProperties(o, properties);
    }
    return o;
  };
}