[TYPO3-core] RFC #0011512: replace while(list()...) by foreach in the TYPO3 core part 1

[Rupert Germann]

Hi,

this is a SVN patch request.

Type: performance improvement

Bugtracker references:
http://bugs.typo3.org/view.php?id=11512

Branches: Trunk

Problem:
foreach() has proven[1] that it is way faster than while(list()=each()) and
in current PHP versions foreach() even needs less memory than while().

Solution:
replace while(list()=each()) with the appropriate foreach() statements in
frontend classes
(part 2 will take care of the rest)


Info:
the patch affects the following files:
t3lib/class.t3lib_page.php
t3lib/class.t3lib_tsparser.php
typo3/sysext/cms/tslib/class.tslib_menu.php
typo3/sysext/cms/tslib/class.tslib_pagegen.php
typo3/sysext/cms/tslib/class.tslib_content.php


thats what I changed:

variant 1
- reset($array);
- while(list($k)=each($array)) {
+ foreach ($array as $k => $v) {

this leaves $v unused but in this way it is faster than while(list()...) or
calling array_keys() before

variant 2
- reset($loadDB->tableArray);
- while(list($table,)=each($loadDB->tableArray)) {
+ foreach ($loadDB->tableArray as $table => $v) {

same as variant 1


variant 3
- reset($Hobjs);
- while(list(,$index)=each($Hobjs)) {
+ foreach ($Hobjs as $index) {


variant 4
- reset($inArray);
- while(list($fN,$fV)=each($inArray)) {
+ foreach ($inArray as $fN => $v) {


in some cases I changed lines where very deep arrays were accessed during
loops to use a local copy of this array instead.


performance gain of this patch depends very much on your sites settings -
will say: if you have a big menu the changes in class.tslib_menu will have
much more impact than with a small one.

I tested it with a (uncached) page which displays 4 tt_news plugins calling
cobj->getmarkerArrayCached() hundreds of times and I got a performance gain
of 7-10% 
The rendering speed of cached pages is not influenced by this patch.

greets
rupert

"There shall be no new TYPO3 version delivering content slower than its
predecessor!"


[1]
http://lists.netfielders.de/pipermail/typo3-dev/2009-June/035735.html [^]