jQuery detection detectng more than jQuery

Question

jQuery detection detectng more than jQuery

aim12340 opened this issue 14 years ago · comments

The jQuery detection here:
if (!$) {
return;
}

detects any $ function as jQuery, which is often not the case. When another $ function exists it passes this test and i then get various other errors below this line.

a good alternative seems to be
if (typeof jQuery == 'undefined') {
return;
}

hope you can include this is the next update

Colin Snover · Answer 1 · Fri Jan 21 2011 03:32:07 GMT+0800 (China Standard Time)

You are reading that code out-of-context. It is valid and correct.

aim12340 · Answer 2 · Fri Jan 21 2011 04:14:55 GMT+0800 (China Standard Time)

can you explain what i'm missing here?

whatever the context, (!$) still lets non-jQuery objects/functions though to code that will cause an error.

unless you mean that TraceKit just isn't supposed to be used except in tightly controlled system where you know (!$) can only be jQuery?

Congrats on an awesomely useful tool BTW.

Colin Snover · Answer 3 · Fri Jan 21 2011 04:36:19 GMT+0800 (China Standard Time)

It is inside an IIFE that defines $ in the local scope to window.jQuery. See lines 1002 and 1117.

aim12340 · Answer 4 · Sat Jan 22 2011 04:08:04 GMT+0800 (China Standard Time)

OK, I see what you mean now. Yes, (typeof jQuery == 'undefined') should be the same as (!$).

I was getting different errors with the 2 different IFs, but now i'll put that down to differences in my visitors, not in the function as it seems the IFs will give the same result.

I'm still getiing errors in the $ and W functions though. I'll start another bug report if i can come up with some useful info.