3v4l.org

run code in 300+ PHP versions simultaneously
<?php error_reporting(-1); echo "ul_u"; define('UL_U', 'foo', true); define('ul_u', 'foo'); echo "\n"; echo "ul_l"; define('UL_L', 'foo'); define('ul_l', 'foo', true); echo "\n"; echo "\n"; echo "lu_l"; define('LU_L', 'foo', true); define('lu_l', 'foo'); echo "\n"; echo "lu_u"; define('LU_U', 'foo'); define('lu_u', 'foo', true);

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57.72 ms | 402 KiB | 5 Q