3v4l.org

run code in 300+ PHP versions simultaneously
<?php $result1 = array_keys(['id' => 1]); // ['id'] $result2 = array_keys(['id' => 1], null); // [] $expected = ['id']; echo $expected === $result1 ? 1 : 0; // 1 true echo $expected === $result2 ? 1 : 0; // 0 false
Output for 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 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 - 8.3.6
10
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29
Parse error: syntax error, unexpected '[', expecting ')' in /in/69EUT on line 2
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected '[', expecting ')' in /in/69EUT on line 2
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `')'' in /in/69EUT on line 2
Process exited with code 255.
preferences:
235.67 ms | 401 KiB | 326 Q