There is no built in method (yet) to check if two variables are references to the same piece of data, but you can do a "reference sniff" test. This is rarely needed, but can be very useful. The function bellow is a slightly modified version of this technique I saw in a forum regarding this comparison limitation.
<?php
function is_ref_to(&$a, &$b)
{
$t = $a;
if($r=($b===($a=1))){ $r = ($b===($a=0)); }
$a = $t;
return $r;
}
$varA = 1;
$varB = $varA;
$varC =&$varA;
var_dump( is_ref_to($varA, $varB) ); var_dump( is_ref_to($varA, $varC) ); ?>
The test above uses a two step process to be 100% generic.
But if you are sure the variables being tested will not be a certain value, example null, then use that value to allow a one step check.
<?php
function is_ref_to_1step(&$a, &$b)
{
$t = $a;
$r=($b===($a=null));
$a = $t;
return $r;
}
?>
