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<?php $a = 1; $a = null; var_dump($a); echo isset($a)? 'true' : 'false',"\n"; unset($a); var_dump($a); echo isset($a)? 'true' : 'false',"\n";
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
NULL false Warning: Undefined variable $a in /in/07kcK on line 7 NULL false
Output for 5.0.4 - 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 - 7.1.10, 7.2.0 - 7.2.33, 7.3.12 - 7.3.31, 7.4.0 - 7.4.33
NULL false Notice: Undefined variable: a in /in/07kcK on line 7 NULL false
Output for 7.3.32 - 7.3.33
NULL false NULL false
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.3
NULL false Notice: Undefined variable: a in /in/07kcK on line 7 NULL false
preferences:
270.15 ms | 402 KiB | 354 Q