Step 3 - Scope Variables

          (function(){
    var foo;

              function foo(){/* 1 */};

              function foo(){/* 2 */};


})();

Scope variables are resolved after functions and unless we forget to assign a value, leaving them undefined, these variables will have a privileged reference. This means that if we declare var foo = null; exactly at the top of above example scope, the latter one will consider foo a null reference.

          (function(){
    alert(foo); // the function!
    // function foo(){/* 2 */}
    var foo = null;
    alert(foo); // null
              function foo(){/* 1 */};

              function foo(){/* 2 */};
    alert(foo); // null
})();

Code Execution