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run code in 500+ PHP versions simultaneously
<?php function foo(&$a, $b) { $a = 'AA'; $b = 'BB'; } $a = 'A'; $b = 'B'; call_user_func_array('foo', array(&$a, $b)); assert($a === 'AA'); assert($b === 'B'); $a = 'A'; $b = 'B'; call_user_func_array('foo', array(&$a, &$b)); assert($a === 'AA'); assert($b === 'B'); $a = 'A'; $b = 'B'; call_user_func('foo', $a, $b); assert($a === 'A'); assert($b === 'B');
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
Warning: foo(): Argument #1 ($a) must be passed by reference, value given in /in/5ojUk on line 27
Output for 5.6.0 - 5.6.23, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33
Warning: Parameter 1 to foo() expected to be a reference, value given in /in/5ojUk on line 27
Output for 7.0.0 - 7.0.20
Warning: assert(): assert($a === 'A') failed in /in/5ojUk on line 29
preferences:
66.5 ms | 1494 KiB | 4 Q