Javascript backtrace

Question

How to I get a backtrace in Javascript?

Ideal features:

• entry function name, or some meaningful identifier for anonymous functions,
• argument list at each level,
• line numbers.

Can this be done in standard ECMAScript?

If not, can it be done in the common web browser dialects?

Thanks.

Edit --

Thanks for your suggestions.

My dialect doesnot support arguments.caller or arguments.callee.

I can do this:

try {
    let x = null;
    x .foo ();
}
catch (e) {
        debug (dump (e.stack));
}

Which gets me the information as a string, which is okay for at-a-glance, but it would be a great help to walk e.stack. Does it have a standard form?

Thanks again.

Stribling

The best way to get strack traces is to use browser based debuggers. – Clepsydra

What is your dialect ? What is dump ? – Clepsydra

It's a proprietry dialect, seems mostly complete, has a few extentions. – Stribling

Answer 1

In my debugging experience, I always use this

(function () { console.log(new Error().stack); })();

As the comments below suggested, the readers should prefer:

console.log(new Error().stack);

Merit

Why the extra function wrapper? can't you just use console.log(new Error().stack);? It worked for me. – Bream

I don't see any reason for the wrapper function either – Egghead

I like clean global scope. So I add a wrapper. – Merit

Adding the wrapper function obviously adds an extra function (pointlessly?) to top of the stack, making the code you care about one step down. I recommend readers don't do this, idk if the poster had a reason for wanting it this way so I won't change the answer. – Ragman

Answer 2

Another way is to use console.trace();

source: https://developer.mozilla.org/en-US/docs/Web/API/Console/trace

Diesis

Answer 3

This lib: stacktrace-js works anywhere, not only with errors.

Example:

StackTrace.get()
    .then(stack => { console.log(stack) })
    .catch(err => { console.log(err) });

Magnify