While debugging javascript, is there a way to alert current call stack?

Question

For simple javascript debugging I'll use alerts to show variable values and the like. Is there a way to get the current call stack in javascript to be able to display it in an alert?

Thanks.

Is this for debugging or production? Im not sure there is any standard way to do this across all browsers, but there might be some useful features specific to only some browsers... — Willi Ballenthin
– Willi Ballenthin, Commented Jan 13, 2010 at 21:20

Jeff Walden · Accepted Answer · 2010-10-04 08:29:36Z

47

Quick and dirty in Gecko-based browsers:

new Error().stack

You can also manually trawl some of the stack using Function.prototype.caller:

var thisFunction = arguments.callee;
var caller = thisFunction.caller;
var callerCaller = caller.caller;
// ...and eventually, assuming no recursion:
var bottomCaller = ...;
assert(bottomCaller.caller === null);

One (possibly large) caveat of the .caller trick is that it doesn't handle recursion -- .caller looks from the top of the stack downward to find the first instance of the function in the stack and then returns its immediate caller, so without being careful you can loop infinitely looking up callers.

Another caveat to caller is that, going forward, if any of your code uses ECMAScript 5's strict mode, the caller property of strict mode functions (or of functions which have themselves been called from strict mode functions) is a so-called "poison pill" which throws a TypeError when accessed. The caller property of "bound" functions (those created by ES5's Function.prototype.bind method) is also a poison pill. These restrictions break the generic stack-walking algorithm, although one could imagine use-specific ways to work around this (entry and exit annotating functions, perhaps).

Do note that stack-walking like this isn't a great idea in production code (as a quick hack for debugging it's fine, tho); at the moment walking up the stack as in the latter example is somewhat expensive in Mozilla's JS engine, and it'll probably throw you out of machine code and back into interpreted code. Also, the stack-walk is O(n²), which might matter if you tend to have complex, deep stacks.

edited Oct 4, 2010 at 8:29

answered Jan 13, 2010 at 21:15

Jeff Walden

7,1182 gold badges41 silver badges55 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

user5132301 Over a year ago

Is this answer still relevant today?

Jeff Walden Over a year ago

Stack-walking isn't quite as expensive as it used to be, but it's still going to hurt perf to a degree. Some of the finer details of how the poison-pill properties function have changed in recent ECMAScript editions, but the overall thrust is mostly the same. Beyond those two bits, the comment remains fundamentally relevant, I think.

Alex Jasmin · Accepted Answer · 2022-02-04 19:22:00Z

42

You can use console.trace()

It doesn't display an alert() but print the stacktrace on the debugger console.

edited Feb 4, 2022 at 19:22

answered Jan 13, 2010 at 22:06

Alex Jasmin

39.5k7 gold badges80 silver badges68 bronze badges

2 Comments

Stefan Haberl Over a year ago

exactly what I was looking for. This is especially useful if you want to dump the call stack while the page is loading.

Andre Kuznetcov Over a year ago

You can use it in Chrome now as well

Ivan Nevostruev · Accepted Answer · 2010-01-13 21:08:58Z

6

Use debugger like Firebug for this if you are in Firefox. Chrome and Opera have build-in debugger. And there are Developers Tools for Internet Explorer.

answered Jan 13, 2010 at 21:08

Ivan Nevostruev

28.9k8 gold badges69 silver badges82 bronze badges

3 Comments

rosscj2533 Over a year ago

Thanks, I am aware of those options, but I was wondering if there was a way to do it without using a debugger.

Ivan Nevostruev Over a year ago

IMO easiest and fastest way to debug javascript is to use debugger.

rosscj2533 Over a year ago

Using a debugger is no problem and usually convenient, I was just looking for a way to look up the call stack in the right situation.

SLaks · Accepted Answer · 2010-01-13 21:10:07Z

3

The best way to debug Javascript is to use Firebug, which includes a full Javascript debugger.

If you're debugging in IE, you can use Visual Web Developer Express (or any other edition of Visual Studio).
If you're debugging IE8, you can use its built-in developer tools, which include a debugger.

It is possible to get the call stack in Javascript; see here.

answered Jan 13, 2010 at 21:10

SLaks

891k182 gold badges1.9k silver badges2k bronze badges

Comments

phatmanace · Accepted Answer · 2010-01-13 21:10:13Z

3

Have you looked at firebug - and a breakpoint. If it's just for debugging, then this might suffice.

Also - you can have a look Here

answered Jan 13, 2010 at 21:10

phatmanace

5,1013 gold badges28 silver badges29 bronze badges

Comments

zvi · Accepted Answer · 2014-09-04 12:16:42Z

1

This will give you all call stack working good for me.

var y = 'arguments.callee.caller';
    while (eval(y) != undefined) {
        stak += eval(y + '.toString()');
        y = y + '.caller';
    }
    alert(stak);

answered Sep 4, 2014 at 12:16

zvi

111 bronze badge

Comments

ptrk · Accepted Answer · 2017-07-26 10:11:40Z

0

For nodejs debugging, in Visual Studio Code, as of v.1.14.2, it's View->Debug (Ctrl+Shift+D)

answered Jul 26, 2017 at 10:11

ptrk

1,8401 gold badge19 silver badges24 bronze badges

Collectives™ on Stack Overflow

While debugging javascript, is there a way to alert current call stack?

7 Answers 7

2 Comments

2 Comments

3 Comments

Comments

Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

7 Answers 7

2 Comments

2 Comments

3 Comments

Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related