Bug #52825 [Opn->Bgs]: return by reference with ternary operator causes notice "Only variable..."

Edit report at http://bugs.php.net/bug.php?id=52825&edit=1 ID: 52825 Updated by: cataphract@php.net Reported by: mbroxer at post dot ru Summary: return by reference with ternary operator causes notice "Only variable..." -Status: Open +Status: Bogus Type: Bug Package: *General Issues Operating System: Windows XP SP3 PHP Version: 5.3.3 Block user comment: N New Comment: return $key > 0 ? $this->a[$key] : $this->b[$key]; is the same as return ($key > 0 ? $this->a[$key] : $this->b[$key]); C is not comparable because it has only pass and return by value. This is documented in http://pt.php.net/ternary : Note: Please note that the ternary operator is a statement, and that it doesn't evaluate to a variable, but to the result of a statement. This is important to know if you want to return a variable by reference. The statement return $var == 42 ? $a : $b; in a return-by-reference function will therefore not work and a warning is issued in later PHP versions. See also http://stackoverflow.com/questions/3389928/can-you-pass-by-reference-while-using-the-ternary-operator/3390182#3390182 Previous Comments: ------------------------------------------------------------------------ [2010-09-13 06:46:55] mbroxer at post dot ru I'm sorry, the expected result and actual result got mixed up when I was submitting. Expected is actual, and actual is expected. ------------------------------------------------------------------------ [2010-09-13 06:45:41] mbroxer at post dot ru Description: ------------ I don't know if it's a bug, or that's how it should be, but it would be logical to assume that a ternary operator is equal to an IF block: return $a ? $b : $c; // == if ($a) return $b; else return $c; I believe that's how it is in C. However when returning a reference, the first version produces a notice: "Notice: Only variable references should be returned by reference" It's hard to tell if this is normal behaviour or not, but it's confusing. If this is normal functionality, then I think this should be in documentation, at least in a form of a comment. Test script: --------------- class test { private $a = array(); private $b = array(); function &getA($key) { return $key > 0 ? $this->a[$key] : $this->b[$key]; // the following line gives no notice // if ($key > 0) return $this->a[$key]; else return $this->b[$key]; } } $a = new test; $b = &$a->getA('1'); Expected result: ---------------- Notice: Undefined index: 1 in - on line 9 Notice: Only variable references should be returned by reference in - on line 9 Actual result: -------------- Notice: Undefined index: 1 in - on line 9 ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/bug.php?id=52825&edit=1