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run code in 300+ PHP versions simultaneously
<?php $a = array(); $b = &$a; $a[] = &$a; $b[] = &$b; var_dump($a === $b); var_dump($a);
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
bool(true) array(2) { [0]=> *RECURSION* [1]=> *RECURSION* }
Output for 5.3.15 - 5.3.29, 5.4.5 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
bool(true) array(2) { [0]=> &array(2) { [0]=> *RECURSION* [1]=> *RECURSION* } [1]=> &array(2) { [0]=> *RECURSION* [1]=> *RECURSION* } }
Output for 4.3.2 - 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 - 5.3.14, 5.4.0 - 5.4.4
Fatal error: Nesting level too deep - recursive dependency? in /in/Zi9pH on line 7
Process exited with code 255.
Output for 4.3.0 - 4.3.1
Fatal error: Nesting level too deep - recursive dependency? in /in/Zi9pH on line 7

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266.93 ms | 401 KiB | 325 Q