Re: References - good or bad

From: Date: Sun, 18 Aug 2002 04:59:36 +0000
Subject: Re: References - good or bad
Groups: php.dev 
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Hi, I've read "PHP 4: Reference Counting and Aliasing" By Andi Gutmans on Zend.com site (http://www.zend.com/zend/art/ref-count.php). Also I read this mail http://marc.theaimsgroup.com/?l=php-dev&m=100955714924477 from him. I would like to know more about how reference is managed by PHP4. I'm missing something like that article (see the first URL) for reference. What happens inside PHP4 with this code ? <? $a = 5; $b = $a; $c = &$b; $d = $c; ?> How PHP4 know that $c and d are reference to $a and not "counted" like $b ? And so what makes references so bad ? ;-) Another (more important) example: <? function foo( $msg ) { $tmp = &$msg; return $tmp; } ?> What happens to $tmp ? If it will not refer to a new memory block why the memory used by the script is more than without '&' ? (See the second URL). Thanks. Ed ___________________________________ Build high quality traffic with the Web's Premier traffic building system. 2 to 1 ratio! http://www.itrafficstar.com/?ref=6

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