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run code in 300+ PHP versions simultaneously
<?php function trues() { foreach(get_defined_constants() as $k => $v) if(strtolower($k) === "true") var_dump($k,$v); } trues(); echo "----\n"; define('True', 3); trues();
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
string(4) "TRUE" bool(true) ---- Warning: Constant True already defined in /in/UIogI on line 10 string(4) "TRUE" bool(true)
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, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.7, 7.2.29 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33
string(4) "TRUE" bool(true) ---- string(4) "TRUE" bool(true) string(4) "True" int(3)
preferences:
188.92 ms | 405 KiB | 308 Q