migrating to jquery 1.4

Question

i would like to upgrade a site from 1.3.2 to 1.4 as i see there are some good performance improvements.

1. can i simply drop this in or should i be concerned about my plugins working?

2. is it backward compatible?

3. what should i be worrying about?

Answer 1

Check this page: http://jquery14.com/day-01/jquery-14

On the bottom there's a list of breaking changes. It will give you an idea if there are issues for you.

There's also a plugin which makes jQuery 1.4 compatible with 1.3.

Answer 2

you should be fine but there are a list of potential issues here:

http://jquery14.com/day-01#backwards

Answer 3

Best bet is to try it and see. jQuery14.com has a backward compatibility list, as well as a 1.3-compat plugin you can use to soften the blow.

Answer 4

I've done the same thing the other day and had no issues. One interestng thing is that the site claims that 1.4 no longer defaults $() to $(document).ready - I do however have such code and it is working fine...