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run code in 300+ PHP versions simultaneously
<?php if (!defined('__DIR__')) { class __FILE_CLASS__ { function __toString() { $X = debug_backtrace(); return dirname($X[1]['file']); } } define('__DIR__', new __FILE_CLASS__); } var_dump(__DIR__);
Output for 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 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 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(3) "/in"
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
<br /> <b>Warning</b>: Constants may only evaluate to scalar values in <b>/in/0rEnK</b> on line <b>9</b><br /> string(7) "__DIR__"
preferences:
315.9 ms | 402 KiB | 468 Q