Item13021: "use strict" is removed when minifying the code

The javascript parser of uglifyjs (our standard minifier) treats "use strict"; as a normal string literal with no use and removes it ... unless you put it in the first column:

(function($) {
"use strict";

   code 
   code 
   code 

})(jQuery);

This affects a lot of JQxxx plugins including JQueryPlugin.

Why bother? Well "use strict"; serves a couple of purposes, i.e.

• forbid some language features that are not secure
• enforce a certain level of code quality, i.e. use of undefined variables
• allows the javascript compiler to optimize the code better

So when the minifier removes "use strict"; then this is actually a very bad thing to happen as it removes these constraints and actually may cost performance as well.

-- MichaelDaum - 02 Sep 2014

Commenting is disabled while not logged in