Is console.log ever undefined?

Question

If there is any case where console.log is undefined, I would need to define it or wrap my logging calls in my own log function.

Is there any javascript runtime environment where console.log could be undefined? By runtime environment I mean a browser or other environments like Node.

http://stackoverflow.com/questions/14086675/which-browsers-support-console-log — Thilo, Apr 26 '17 at 09:20
The question is very general on purpose, to include runtime environments like browsers, Node, or something else. — Arne Evertsson, Apr 26 '17 at 09:34

score 2 · Answer 1 · edited May 23 '17 at 12:02

In IE9-, console.log only exists when the developer console is openned.

If you need to logs in those browsers, it may be a good idea to deactivate console or to test before logging.

To make console.log works on those old browsers, a tricky but smart way is to set at the start of your JS this code:

if (!window.console) window.console = {};
if (!window.console.log) window.console.log = function() {};

^{Credits to Michael Erickson}

For further details, here is a very complete blog about cross-browser compatibility.

Is console.log ever undefined?

1 Answers1