Bug->Req #63862 [Opn]: Passing by reference: func($a = $b);

From: Date: Sat, 05 Jan 2013 10:35:17 +0000
Subject: Bug->Req #63862 [Opn]: Passing by reference: func($a = $b);
References: 1  Groups: php.doc.bugs 
Request: Send a blank email to doc-bugs+get-9354@lists.php.net to get a copy of this message
Edit report at https://bugs.php.net/bug.php?id=63862&edit=1 ID: 63862 User updated by: bobwei9 at hotmail dot com Reported by: bobwei9 at hotmail dot com Summary: Passing by reference: func($a = $b); Status: Open -Type: Bug +Type: Feature/Change Request Package: Documentation problem Operating System: Mac OS X Mountain Lion PHP Version: master-Git-2012-12-27 (Git) Block user comment: N Private report: N New Comment: Yeah, it is primarily not documented, but is there a reason why not to change behavior? I don't think that it'll introduce a BC break, because it makes today no sense to write such a code. (Throws E_STRICT error) I mean: if there is a $variable = on the beginning of an argument and the argument expects a reference, then evaluate first the part after the first =, assign the result to the $variable and pas this variable by reference. Or requires this minor change to be a rfc...? Previous Comments: ------------------------------------------------------------------------ [2013-01-05 05:09:45] laruence@php.net $a = $b result a tmp value, not the left variable self. I wrote a simple explaination for this before, (however it's in chinese) http://www.laruence.com/2010/01/03/1225.html change to doc problem instead ------------------------------------------------------------------------ [2012-12-31 22:52:06] bobwei9 at hotmail dot com I know how it works now, but I don't know if it is intended (It isn't documented.) Then I wish that the first variable $a = $b = $c; is passed by array. ------------------------------------------------------------------------ [2012-12-31 22:06:57] mail+php at requinix dot net FYI: Expected behavior. The "value" of an assignment is just a value and not a reference to a variable, just like how "true?$a:$b" is the value of $a and not actually the variable $a. I don't think it would be so difficult to change that behavior but I'm afraid of the consequences it might have. There's also a more subtle change that would be required for your shorthand to work. Assignment currently propagates the right-most operand: $a=$b=$c is almost equivalent* to $b=$c;$a=$c; and not $b=$c;$a=$b; Unless that changes as well then sort($array=[3,1,2]) would try to sort the [3,1,2] and not $array. * $c is evaluated only once ------------------------------------------------------------------------ [2012-12-27 16:57:06] bobwei9 at hotmail dot com Description: ------------ I don't know if this should be considered as a bug or as expected behaviour (=> feature request). When passing an assignment to a function which expects a variable as reference like sort(), then an E_STRICT message is issued and nothing has changed. What I want, is that a code like "sort($a = $b);" is executed in the same way as "$a = $b; sort($a);". This could help to reduce the number of little, unnecessary lines. Test script: --------------- php -r 'sort($array = [3,1,2]); var_dump($array);' Expected result: ---------------- array(3) { [0]=> int(1) [1]=> int(2) [2]=> int(3) } Actual result: -------------- Strict Standards: Only variables should be passed by reference in Command line code on line 1 array(3) { [0]=> int(3) [1]=> int(1) [2]=> int(2) } ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=63862&edit=1

« previous php.doc.bugs (#9354) next »