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<?php $a = NULL; $b = NULL; $c = NULL; var_dump(isset($a)); var_dump(isset($b)); var_dump(empty($c)); var_dump(empty($d)); var_dump($d);
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
bool(false) bool(false) bool(true) bool(true) Warning: Undefined variable $d in /in/m9i8l on line 11 NULL
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, 5.5.24 - 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 - 7.3.31, 7.4.0 - 7.4.33
bool(false) bool(false) bool(true) bool(true) Notice: Undefined variable: d in /in/m9i8l on line 11 NULL
Output for 7.3.32 - 7.3.33
bool(false) bool(false) bool(true) bool(true) NULL
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.3
bool(false) bool(false) bool(true) bool(true) Notice: Undefined variable: d in /in/m9i8l on line 11 NULL
preferences:
243.88 ms | 402 KiB | 329 Q