Call constructor using an arguments object in javascript?

Question

Is it possible to call the constructor using an arguments object?

var MyClass = function(a, b){
  this.a = a;
  this.b = b;
};
var myClassInstance = function(){
  //This line would not work, but is what I'm asking. Is there a way besides eval?
  return new MyClass.apply(?, arguments);
}('an A value', 'a B value');

Answer 1

Yes, you could do this:

var myClassInstance = function(){
  return MyClass.apply(Object.create(MyClass.prototype), arguments);
}('an A value', 'a B value');

Answer 2

Yes it is.

However, I had to rewrite your code a bit, as the method you're currently using appears to put the function calls into the global scope.

function MyClass(a, b){
    this.a = a;
    this.b = b;
};

function myClassInstance(){

    //The apply function will apply MyClass attributes to this object.
    //The apply function itself returns nothing.
    MyClass.apply(this, arguments);
    console.log(this); //Should show the a and b variables

    return this;
}

new myClassInstance('an A value', 'a B value');