Function Arguments Passing and Return

Question

  var foo = {
    bar: function() { return this.baz; },
    baz: 1
  };
  (function(){
    return typeof arguments[0]();
  })(foo.bar);

Why does this c

Answer 1

the code won't work because inside the anonymous function you lose the reference to this.baz of foo object when used in another context

you can use the apply() method to redefine the context, like so

var foo = {
   bar: function() { return this.baz; },
   baz: 1
};

(function(){
   return arguments[0].apply(foo);
})(foo.bar);

and this returns correctly 1 because apply() method change the execution context to the object passed as argument

typeof arguments[0].apply(foo);

returns numberas expected