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What References Are Not

What References Are Not

As said before, references are not pointers. That means, the following construct won't do what you expect:

<?php function foo(&$var) {     $var =& $GLOBALS["baz"]; } foo($bar  ?>

What happens is that $var in foo will be bound with $bar in the caller, but then re-bound with $GLOBALS["baz"]. There's no way to bind $bar in the calling scope to something else using the reference mechanism, since $bar is not available in the function foo (it is represented by $var, but $var has only variable contents and not name-to-value binding in the calling symbol table). You can use returning references to reference variables selected by the function.

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