note 77998 added to language.operators.increment

From: Date: Sun, 23 Sep 2007 10:04:26 +0000
Subject: note 77998 added to language.operators.increment
Groups: php.notes 
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Speed tip: Do not use post-incrementation/post-decrementation ($i++, $i--) where you do not work with the result of this expression. (For novices: Yes, every expression returns an result, also $a = '5' returns result, same as $a && $b. And this consumes more time and resources.) When writing loops, replace the post-incrementation with pre-incrementation, it is around 3times faster than post-incrementation. Why? In post-incrementation, PHP needs to copy variable value somewhere, then it increments the value, then returns the value which was stored before the incrementation was done. No matter if you don't expect the return value, PHP is scripting language, not compiled one, so it doesn't optimize use of return values. <?php // Good practice for loop: $array_count = count($array); // Store temporarily instead of calling everytime in loop for ($i = 0; $i < $max_count; ++$i) { // Use pre-incrementation here, it is faster // do something here } ?> ---- Server IP: 69.147.83.197 Probable Submitter: 83.208.62.60 ---- Manual Page -- http://www.php.net/manual/en/language.operators.increment.php Edit -- https://master.php.net/note/edit/77998 Del: integrated -- https://master.php.net/note/delete/77998/integrated Del: useless -- https://master.php.net/note/delete/77998/useless Del: bad code -- https://master.php.net/note/delete/77998/bad+code Del: spam -- https://master.php.net/note/delete/77998/spam Del: non-english -- https://master.php.net/note/delete/77998/non-english Del: in docs -- https://master.php.net/note/delete/77998/in+docs Del: other reasons-- https://master.php.net/note/delete/77998 Reject -- https://master.php.net/note/reject/77998 Search -- https://master.php.net/manage/user-notes.php

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