Scope page

Learn how to see the variables available in the scope.

The problem

What is the value of VARIABLE_IN_SCOPE in the following code?

<script src="//bitovi.github.io/academy/static/scripts/debugging/variables.js"></script>
<script type="module">
// What is the value of VARIABLE_IN_SCOPE?
function a(){
    var a = makeAVariables;
    return function b(){
        var VARIABLE_IN_SCOPE = makeBVariables;
        return function c(){
            var c = makeCVariables;
            return function d(){
                var d = makeDVariables;
                console.log("What is the value of VARIABLE_IN_SCOPE?");
                debugger;
                eval("");
            };
        };
    };
}
a()()()();
</script>

What you need to know

Chrome’s developer tools allow you to inspect variables in the scope. For example, consider the following code from the Closures training:

function counter(){

  var count = 0;

  return function(){
    debugger;
    return ++count;
  };

};

var c1 = counter();

c1();

c1();

var c2 = counter();

c2();

Chrome’s developers tools allows you to inspect variables in the scope as follows:

The solution

Click to see the answer

The answer is d.