3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a[1425328718] = 'ryat'; $a['attachment'] = 'hi'; unset($a['attachment']); //unset($a[1425328718]); var_dump($a['attachment']);
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
Warning: Undefined array key "attachment" in /in/RV4F3 on line 6 NULL
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.32, 5.6.34 - 5.6.38, 5.6.40, 7.0.0 - 7.0.30, 7.0.32 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33
Notice: Undefined index: attachment in /in/RV4F3 on line 6 NULL
Output for 7.3.32 - 7.3.33
NULL
Output for 5.6.33, 5.6.39, 7.0.31

Process exited with code 137.
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
Notice: Undefined index: attachment in /in/RV4F3 on line 6 NULL

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271.58 ms | 402 KiB | 456 Q