#28704 [Bgs]: strange behaviour with references

ID: 28704 Updated by: et@php.net Reported By: spy at spy dot zp dot ua Status: Bogus Bug Type: Scripting Engine problem Operating System: FreeBSD-4.x PHP Version: 4.3.6 New Comment: http://de.php.net/manual/en/language.references.whatdo.php "Note: If array with references is copied, its values are not dereferenced. This is valid also for arrays passed by value to functions." Previous Comments: ------------------------------------------------------------------------ [2004-06-30 15:17:32] spy at spy dot zp dot ua Of course, I have checked manual, much more then twice. Sorry, if you have no enough time to understand, that it is either real bug, or a problem to be discussed and solved. And I have no time to dig into source code to find out causes. ------------------------------------------------------------------------ [2004-06-30 03:43:59] moriyoshi@php.net Thank you for taking the time to write to us, but this is not a bug. Please double-check the documentation available at http://www.php.net/manual/ and the instructions on how to report a bug at http://bugs.php.net/how-to-report.php See http://bugs.php.net/bug.php?id=20993&edit=3 ------------------------------------------------------------------------ [2004-06-09 01:34:02] spy at spy dot zp dot ua Description: ------------ As shown in this example, the elements of $a become a references during "for" cycle, although there are not have any aliases to their values. If we make a copy ($b=$a) of an array, it becomes an array of references too. And only if we unset the copy ($b), engine founds that $a elements are not really referenced by another vars. The same result we can get with foreach($a), (because foreach works with a copy of an array as noted in Bug #24486) BTW, how can I make a really clean COPY of an array, including all of it elements? And it should be useful to have a method to test if variable have a reference(s). Reproduce code: --------------- $a = array(1, 2, 3); for ($i = 0; $i < count($a); $i++) { $x =& $a[$i]; } $x=&$nowhere; print "Dump 1 =>"; var_dump($a); $b=$a; $b['0']=6; $b['1']=7; $b['2']=8; print "Dump 2 =>"; var_dump($a); unset($b); print "Dump 3 =>"; var_dump($a); Expected result: ---------------- I don't know what to expect at all now =) Before today I should expect all dumps like this: Dump * =>array(3) { [0]=> int(1) [1]=> int(2) [2]=> int(3) } Actual result: -------------- Dump 1 =>array(3) { [0]=> &int(1) [1]=> &int(2) [2]=> &int(3) } Dump 2 =>array(3) { [0]=> &int(6) [1]=> &int(7) [2]=> &int(8) } Dump 3 =>array(3) { [0]=> int(6) [1]=> int(7) [2]=> int(8) } ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=28704&edit=1