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run code in 300+ PHP versions simultaneously
<?php namespace { define('true', false); // Notice: Constant true already defined var_dump(true === false); //false } namespace Knp { define('Knp\\true', false); var_dump(true === false); // true in php5 }
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.7
Warning: Constant true already defined in /in/DjLKE on line 4 bool(false) bool(false)
Output for 7.0.0 - 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: Constant true already defined in /in/DjLKE on line 4 bool(false) bool(false)
Output for 7.3.32 - 7.3.33
bool(false) bool(false)
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40
Notice: Constant true already defined in /in/DjLKE on line 4 bool(false) bool(true)
preferences:
263.15 ms | 402 KiB | 377 Q