3v4l.org

run code in 300+ PHP versions simultaneously
<?php function foo(){ return "Foo \n"; } $foo = 'foo'; var_dump($foo); // string(3) "foo" echo $foo(); // NULL. Why?
Output for 7.1.25 - 7.1.28, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.30, 8.0.0 - 8.0.22, 8.1.0 - 8.1.9
string(3) "foo" Foo

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16.77 ms | 409 KiB | 5 Q