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<?php error_reporting(-1); function myCheck($in) { return isset($in); } $var1='Something'; $var2='var1'; echo 'Set:' . isset($$var2); $var2='nope'; echo 'Set:' . isset($$var2); $var2='var1'; echo 'Set:' . myCheck($$var2); $var2='nope'; echo 'Set:' . myCheck($$var2); ?>
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
Set:1Set:Set:1 Warning: Undefined variable $nope in /in/DcEqM on line 19 Set:
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 - 5.5.35, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33
Set:1Set:Set:1 Notice: Undefined variable: nope in /in/DcEqM on line 19 Set:
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.3
Set:1Set:Set:1 Notice: Undefined variable: nope in /in/DcEqM on line 19 Set:

preferences:
257.63 ms | 402 KiB | 345 Q