3v4l.org

run code in 300+ PHP versions simultaneously
<?php //namespace Foo; const TRUE=false; if (TRUE) { echo "TRUE"; } else { echo "FALSE!!!"; }
Output for 5.3.0 - 5.3.23, 5.4.0 - 5.4.13
Fatal error: Cannot redeclare constant 'TRUE' in /in/4ZhKL on line 3
Process exited with code 255.
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174.83 ms | 1399 KiB | 45 Q