3v4l.org

run code in 300+ PHP versions simultaneously
<?php interface Foo { public function bar($foo); } class One implements Foo { public function bar($foo): bool { } }
Output for 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 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 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Output for 5.6.0 - 5.6.40
Parse error: syntax error, unexpected ':', expecting ';' or '{' in /in/gk7tH on line 8
Process exited with code 255.

preferences:
243.85 ms | 401 KiB | 283 Q