3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = array( 'foo' => null, 'bar' => '', 'baz' => FALSE, ); echo 'foo: ' . (string) isset($array['foo']); echo "\n"; echo 'bar: ' . (string) isset($array['bar']); echo "\n"; echo 'baz: ' . (string) isset($array['baz']); echo "\n"; echo 'fizz: ' . (string) isset($array['fizz']);
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, 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 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 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 - 8.3.7
foo: bar: 1 baz: 1 fizz:
preferences:
222.77 ms | 406 KiB | 372 Q