Comments on: Work with gzip, not against it

By: Paul Irish

Paul Irish — Fri, 04 Sep 2009 08:28:52 +0000

Based on Ywg’s comments on Andrea’s post: http://webreflection.blogspot.com/2009/02/on-my-vicious-javascript-code.html

… I’m starting to believe the dictionary reduction wouldn’t be all that successful. However I would certainly think this should happen from within the YUI Compressor, and not manually.

By: Kean

Kean — Thu, 03 Sep 2009 22:57:16 +0000

@Paul The optimization that you talked about can possibly be done but I predict that they will run into unforeseen problems if they do that.

By: Kean

Kean — Thu, 03 Sep 2009 22:51:54 +0000

@Craig I agree with you, we should sit back, relax and let gzip do its job. This will make the code more readable and you don’t have to do the extra work.

By: Craig

Craig — Thu, 03 Sep 2009 18:33:17 +0000

I’m rather curious… have you guys heard of over-optimization?

You’re making your code much harder to work with (in terms of maintenance and initial authoring) to save (literally!) a few bytes.

This conversation is fascinating from a computer science perspective (I love thinking about this stuff, too), but the cost is incredibly high. If anything, the fruits of this research should appear as improvement to YUI Compressor and other minifiers, and *definitely* not as a guide for day-to-day javascript programmers.

By: Paul Irish

Paul Irish — Thu, 03 Sep 2009 18:24:14 +0000

More detail: The idea is to identify the javascript keywords that are in use and can be use legally as variable names (not reserved words or anything). Sort according to string size. Use those up and then go back to A, B, C, D, etc.

So:
Input:
(function(htmlelem,className){htmlelem[className]= htmlelem[className].replace(/\bnojs\b/,’js’)})(document.documentElement,’className’);

current output:
(function(B,C){B[C]=B[C].replace(/\bnojs\b/,’js’)})(document.documentElement,’className’);

proposed output:
(function(document,replace){document[replace]=document[replace].replace(/\bnojs\b/,’js’)})(document.documentElement,’className’);

Based on gzip’s technology I think this could be a measurable win for gzip-enabled agents. Thoughts?

By: Paul Irish

Paul Irish — Thu, 03 Sep 2009 04:12:23 +0000

If this is true, then I’d say we’d get optimal results if we, as developers, munged our strings, but our minifiers rename the variables to (un-minifiable) strings already in use:
constructor, length, nodeName, script, break, slice, etc.

Would make the compressed source reallllly hard to follow but I think it’d lead to savings after gzip, yes?