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<?php function modify(&$x) { $x = 50; } function &get_reference() { global $x; return $x; } $x = 42; var_dump($x); modify(get_reference()); var_dump($x); print "======"; $x = 42; var_dump($x); modify((get_reference())); // brackets var_dump($x); ?>
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.1, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
int(42) int(50) ======int(42) int(50)
Output for 5.2.1 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.37
int(42) int(50) ======int(42) Strict Standards: Only variables should be passed by reference in /in/oJ407 on line 18 int(42)
Output for 5.1.2 - 5.1.6, 5.2.0
int(42) Strict Standards: Only variables should be passed by reference in /in/oJ407 on line 13 int(42) ======int(42) Strict Standards: Only variables should be passed by reference in /in/oJ407 on line 18 int(42)

preferences:
239.14 ms | 402 KiB | 350 Q