// prevent errors on non-firebug browsers

(function() {
	var f = function() {};
	var c = {
		info: f,
		log: f,
		assert: f,
		warn: f,
		error: f,
		dir: f,
		group: f,
		groupEnd: f
	};

	if(!window.console)
		window.console = c;
})();

prevent errors on non-firebug browsers

Firebug console log proxy

javascript

JavaScript