3v4l.org

run code in 300+ PHP versions simultaneously
<?php define('CL', function () { echo "hello\n"; }); class Foo { public const \Closure CL = CL; } (Foo::CL)();
Output for 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
hello
Output for 8.1.0 - 8.1.34, 8.2.0 - 8.2.30
Parse error: syntax error, unexpected fully qualified name "\Closure" in /in/F2VKn on line 7
Process exited with code 255.

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