Call Stack page

Learn how to trace how functions are called.

The problem

What is the name of the function that calls the end function below?

<script src="//bitovi.github.io/academy/static/scripts/debugging/variables.js"></script>
<script type="module">
function end() {
    console.log("What is the name of the function that calls end?");
    debugger;
}
start();
</script>

What you need to know

In the following code, a() calls b(), b() calls c(), and c() calls d():

function a(){
    var varA = "A";
    b();
}
function b(){
    var varB = "B";
    c();
}
function c(){
    var varC = "C";
    d();
}
function d(){
    var varD = "D";
}
a();

By adding a breakpoint in d(), you will see the following in the Call Stack:

Chrome can also track asynchrounous function calls. In the following code, setTimeout is used to call the next function:

function a(){
    setTimeout(b,10);
}
function b(){
    setTimeout(c,10);
}
function c(){
    setTimeout(d,10);
}
function d(){
    console.log("d");
}
a();

By adding a breakpoint in d(), you will see the following in the Call Stack:

The solution

Click to see the answer

The answer is e.

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