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<?php $discoveredAt; if (isset($discoveredAt)) { echo "Set as Null" . PHP_EOL; } else { echo "Not set: NULL" . PHP_EOL; } $discoveredAt = ""; if (empty($discoveredAt)) { echo "Set as empty string" . PHP_EOL; } else { echo "Not set: empty string" . PHP_EOL; }
Output for 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 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.16, 8.3.0 - 8.3.3
Not set: NULL Set as empty string
Output for 5.0.4 - 5.0.5
Notice: Undefined variable: discoveredAt in /in/t6n6p on line 3 Not set: NULL Set as empty string
Output for 4.3.10 - 4.3.11, 4.4.0 - 4.4.9, 5.0.2 - 5.0.3
Notice: Undefined variable: discoveredAt in /in/t6n6p on line 3 Not set: NULL Set as empty string
Output for 4.3.0 - 4.3.9, 5.0.0 - 5.0.1
Notice: Undefined variable: discoveredAt in /in/t6n6p on line 3 Notice: Use of undefined constant PHP_EOL - assumed 'PHP_EOL' in /in/t6n6p on line 8 Not set: NULLPHP_EOL Notice: Use of undefined constant PHP_EOL - assumed 'PHP_EOL' in /in/t6n6p on line 14 Set as empty stringPHP_EOL

preferences:
306.05 ms | 403 KiB | 450 Q