jQuery and Firefox Firebug

If you use an older Firefox with any version of Firebug, some versions of jQuery produce Javascript errors and some of the jQuery developers made the stupid decision to not fix the errors. It is the old Luddite thinking from the 1960s. Fortuantely the error is gone from the current version of Firefox with the current version of jQuery. Update if you strike errors.

In every programming language there is a way to define variables even if they are called something else. Many languages start off with the assumption that they can automatically create variables without the programmer defining them. As soon as anyone works on a big program, they realise the sloppy approach of automatic variable creation produces programs containing errors that are extremely hard to find. You can then change your programming language to require explicit definition of variables and add code to detect incorrect use.

Javascript is a sloppy language that has not improved much with age despite frequent rewrites and attempts to standardise the language. The people at Mozilla decided Firefox should attempt to highlight the rubbish in most Javascript code by issuing warning messages about the really stupid assumptions made in a lot of Javascript code. When you switch on Firebug in Firefox and use Javascript code, Firebug passes on the warnings.

Most of the Javascript libraries are full of crud. jQuery starts off lean and clean but still has some false assumptions. Some of the people developing jQuery decided to fix the bad assumptions in jQuery then suddenly they decided to leave the stupidities untouched. There are elegantly written pages explaining why they decided to leave errors in the code. You know the typical logic.

We always fall down the stairs when we go outside. Why do you suggest we fix the stairs?

Every time we serve puffer fish in our restaurant, customers die. Why should we change our menu?

A few tiny code changes in jQuery would keep it clean, lean, and make it one of the rare Javascript libraries where everything happens reliably, where everything happens predictably, and where extensions work because there are no false assumptions.

How to you avoid the error alerts from Firefox?

There is an option you can turn off in Firefox to tell Firefox to not report false assumptions in Javascript. If you do that, you will not see the warnings from the code you develop.

How to you avoid the error alerts from Firebug?

You can switch off Firebug before loading a page containing jQuery then switch Firebug back on after the page load. You can also leave Firebug on but switch off Firebug monitoring of scripts. Both work for normal web development. Neither work when you are developing a Javascript script that uses jQuery.