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Subject: Re: Confusing pointers in PHP 4 and 5
From: bert@procurios.nl (Bert Slagter)

Sara Golemon wrote:
> Every "variable" in PHP is a pair. 
 >
 > [cut]
> 
> $foo = 1;
> 
> /*    $foo (label)  -------->    1 (value) (is_ref=0, refcount=1)   */
> 
> $bar = &$foo;
> 
> /*   $foo (label) ---------->    1 (value)  */
> /*   $bar (label) -------/         is_ref=1, refcount=2 */
> 
> Hope that helps.
> 
> -Sara

Thanks for the clear explanation :). I understood that in PHP 5 objects 
are automatically referenced when assigned, and 'primary types' like 
int, bool, string are normally copied when assigned.

When I do a (very rough) benchmark with strings/ints, assigning (and 
thus copying) a 1000 bytes string isn't significantly slower than 
referencing it. Also: memory usage is exactly the same.

Is there any situation in which one might *manually* want to reference a 
variable instead of assigning it (like: $x =& $y)?

Bert