Take the 2-minute tour ×
Programmers Stack Exchange is a question and answer site for professional programmers interested in conceptual questions about software development. It's 100% free, no registration required.

I have seen code like this in several places:

(function() {
    var method;
    var noop = function noop() {};
    var methods = [
        'assert', 'clear', 'count', 'debug', 'dir', 'dirxml', 'error',
        'exception', 'group', 'groupCollapsed', 'groupEnd', 'info', 'log',
        'markTimeline', 'profile', 'profileEnd', 'table', 'time', 'timeEnd',
        'timeStamp', 'trace', 'warn'
    var length = methods.length;
    var console = (window.console = window.console || {});

    while (length--) {
        method = methods[length];

        // Only stub undefined methods.
        if (!console[method]) {
            console[method] = noop;

Specifically I am interested in this line of code

var console = (window.console = window.console || {});

Why are we creating a new window.console object if window.console is not defined ?

So why are we setting window.console={}?

share|improve this question

1 Answer 1

This creates a dummy windows.console for older browsers to prevent them from throwing errors. First an empty function is created and then the missing function calls are added (without any real functionality).

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.