note 40515 added to function.get-object-vars

more strange, strange behaviour: if you are trying to deep-copy an object with get_object_vars(), strange behaviour can accidentally clobber your original object properties. please read very, very carefully: get_object_vars() may either return references to *or* deep copies of the object's properties *depending on whether that property has been set with the -> operator*. (this behaviour probably varies per php platform and os so please confirm for yourself.) furthermore, consider $properties = get_object_vars($obj); normally, unset()ting a reference does not affect the original, i.e. $ref = NULL; is not the same as unset($ref); per the references documentation. However, if you have this strange references version and you unset() an array element of $properties, it will *SET THE OBJECT PROPERTY TO NULL*, which is not how references normally work. even stranger behaviour comes into effect that i can only express with an example. please test this with your version and OS and proceed very carefully: --> <?php echo "<pre>\n"; class Lump { var $size = 'average'; function & copy() { // return a deep copy $copy = new Lump(); $properties = get_object_vars($this); foreach( array_keys( $properties ) as $property ){ $copy->$property = $properties[$property]; // deep, right? } return $copy; } } $lump = new Lump(); $lump->size = 'huge'; // <--- this line changes everything // comment above line out, and see the difference // also, try substituting another property for 'size' $properties = get_object_vars($lump); $properties['size'] = 'small'; // this behavior varies echo "after changing the properties array:\n"; var_dump( $lump ); // it's either big or small (never huge) depending on // whether you commented-out the indicated line //------------- let's try using our copy() method $original_lump = new Lump(); $original_lump->size = 'huge'; // this line changes the behaviour $other_lump =& $original_lump->copy(); unset( $other_lump->size ); echo "after unsetting in copy:\n"; var_dump( $original_lump ); // i'm afraid so -- original value clobbered ! echo "</pre>\n"; ?> code till dawn, mark meves ---- Manual Page -- http://www.php.net/manual/en/function.get-object-vars.php Edit -- http://master.php.net/manage/user-notes.php?action=edit+40515 Delete -- http://master.php.net/manage/user-notes.php?action=delete+40515&report=yes Reject -- http://master.php.net/manage/user-notes.php?action=reject+40515&report=yes Search -- http://master.php.net/manage/user-notes.php