pjs/toolkit/components/console
timeless%mozdev.org 109888ebc5 Bug 348627 O(N^2) or worse algorithm in error console
r=bz sr=bz

Perhaps an explanation. String concatenation is a chance for garbage collection.
If you have unbounded input, this can be pretty bad. When you start running low
on memory, the garbage collector gets desperate and won't take shortcuts. Worst of
all, the original code generates one string of garbage every iteration starting with
the second or third.

This code uses a=[] to construct an array and a[n] to set the upper array boundary,
0 being the lower, and there are n slots between a[0] and a[n].
join() will build a string with n copies of the join argument, where n is the number                                                        of slots between between cells. So for:
a=[]; a[1]=''; there's 1 slot between [0] and [1]. The array's length is actually 2,
but the joined length will be 1.

While it is possible to use new Array(x), the behavior is different because the
array has length x and there are x-1 spaces between cells. This leads to code which
would be both much longer and harder to read. And definitely not particularly
intuitive.

The code used here otoh, while magical will hopefully require you to pause, think,
and quickly understand what's going on. If not, you paused long enough for this
bubble to appear and explain it to you :).
2006-08-14 22:03:34 +00:00
..
content Bug 348627 O(N^2) or worse algorithm in error console 2006-08-14 22:03:34 +00:00
.cvsignore
Makefile.in Bug 236613: change to MPL/LGPL/GPL tri-license. 2005-02-01 17:07:35 +00:00
jar.mn Bug 328932: Evaluating Components.classes in JS Console throws an exception, r=bzbarsky, sr=jag 2006-03-03 00:48:52 +00:00
jsconsole-clhandler.js Bug 338899: be nice to -jsconsole (no duplicate windows, no unrequested windows), patch by Simon B�nzli <zeniko@gmail.com>, r=mconnor 2006-06-04 07:14:10 +00:00