TYPO3 Core

Wolfgang, your our optimization hero. What do you think of this?

Here are some numbers:

-----------------
Result *old*: 39.97
-----------------
Result *new*: 28.69
-----------------

Excuse me Wolfgang, but what do these numbers explain ?
Is there any "benchmarking protocol" for Typo3 ?

Running a (quite minimalist) page in typo3 4.0, I used xDebug profiling traces in winCacheGrind to find most-used/most-time-consuming methods =>
OLD trimExplode: total Cumulative Time = 1.68%
NEW trimExplode: total Cumulative Time = 0.24%

I didn't look at the code but it must be completely certain that indexes in the array are numerical from 0 and forward plus that removed values are string compared - not just =="" or so.

Unless this is absolutely sure that it is 110% compatible its a -1. I take no chances with that function.

Sorry, the code was only "10% compatible"...
Keys didn't start from zero, if NonEmptyValues=1 and an EmptyValues was present at the beginning of the list.
(Anybody wants to write a unit test for t3lib_div, ... during his next holidays ? ;-)

THE CODE SHOULD BE (Tested with PHP 4.4.2 and PHP 5.1.2) :
function trimExplode($delim, $string, $onlyNonEmptyValues=0) {
if ($onlyNonEmptyValues) {
return array_merge(array_diff(array_map('trim', explode($delim, $string)), array('')));
} else {
return array_map('trim', explode($delim, $string));
}
}

And here is a better test (uses var_export() to compare arrays) :

error_reporting(E_ALL);
class t3lib_div {
/** * Explodes a string and trims all values for whitespace in the ends. * If $onlyNonEmptyValues is set, then all blank ('') values are removed. * Usage: 256 * * @param string Delimiter string to explode with * @param string The string to explode * @param boolean If set, all empty values (='') will NOT be set in output * @return array Exploded values
*/
function trimExplode($delim, $string, $onlyNonEmptyValues=0) {
$res1 = t3lib_div::trimExplodeOLD($delim, $string, $onlyNonEmptyValues);
$res2 = t3lib_div::trimExplodeNEW($delim, $string, $onlyNonEmptyValues);

//*** strict array compare 
        $res1export = var_export($res1, true);
        $res2export = var_export($res2, true);
        if ($res1export !== $res2export) {
            trigger_error('trimExplode() New implementation failed.', E_USER_WARNING);
            t3lib_div::debug($string, 'TEST ($onlyNonEmptyValues='.($onlyNonEmptyValues?'1':'0').') $string');
            t3lib_div::debug($res1export, 'trimExplodeNEW() error $res1export');
            t3lib_div::debug($res2export, 'trimExplodeNEW() error $res2export');
        }

return $res1;
    }
    function trimExplodeNEW($delim, $string, $onlyNonEmptyValues=0)    {
        if ($onlyNonEmptyValues) {
            return array_merge(array_diff(array_map('trim', explode($delim, $string)), array('')));
        } else {
            return array_map('trim', explode($delim, $string));
        }
    }
    function trimExplodeOLD($delim, $string, $onlyNonEmptyValues=0)    {
        $temp = explode($delim,$string);
        $newtemp=array();
        while(list($key,$val)=each($temp))    {
            if (!$onlyNonEmptyValues || strcmp('',trim($val)))    {
                $newtemp[]=trim($val);
            }
        }
        reset($newtemp);
        return $newtemp;
    }

function debug($msg, $title) {
        print $title.': '.$msg."\n";
    }

}

$tests = array(
', a, 1 ,c ,dddd , ,',
", 0, , \n , , aaa , 00,",
'1,2,3,4,5.6,7,8,9,10,11',
implode(',', array_fill(0, 1000, 'test')),
implode(' , ', array_fill(0, 100, 'test')),
' ,, ,,'.implode(' , ', array_fill(0, 100, 'test')).',, ,, ',
' ,, ,,'.implode(' , , ', array_fill(0, 100, 'test')).',, ,, ',
implode(',', range(0, 1000)),
implode(' , ', range(0, 1000)),
);

print "

\n";
foreach ($tests as $test) {
    foreach (array(true, false) as $onlyNonEmptyValues) {
        $res = t3lib_div::trimExplode(',', $test, $onlyNonEmptyValues);
    }
}
print "

?>

Another version:

function trimExplodeMASI($delim, $string, $onlyNonEmptyValues=0) {
        $array = explode($delim, $string);
        if ($onlyNonEmptyValues) {
            foreach($array as $index => &$value) {
                $value = trim($value);
                if ($value == '') {
                    unset($array[$index]);
                }
            }
            $array = array_merge($array);
        } else {
            foreach($array as $key => &$value) {
                $value = trim($value);
            }
        }
        return $array;
    }

Using the arrays from the unit test my test (using t3lib_dib::milliseconds for emseauring) I get the follwing numbers (in ms):

OLD: 45
NEW: 26
MASI: 23

Version from comment #14928 has been commited to SVN.