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run code in 300+ PHP versions simultaneously
<?php function & do_something(& $arg) { $arg = 'func'; return $arg; } $a = 'init'; $b = do_something($a); $b = 'fin'; var_dump($a, $b); $x = 'init'; $y = & do_something($x); $y = 'fin'; var_dump($x, $y);
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
string(4) "func" string(3) "fin" string(3) "fin" string(3) "fin"

preferences:
258.3 ms | 405 KiB | 398 Q