3v4l.org

run code in 300+ PHP versions simultaneously
<?php $s = '012345'; var_dump( ord('0') !== ord($s[0]), ord('0'), ord($s[0]), ini_get('opcache.optimization_level') );
Output for 7.3.0 - 7.3.31, 7.4.0 - 7.4.32, 8.0.0 - 8.0.12, 8.0.14 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
bool(false) int(48) int(48) string(10) "0x7FFEBFFF"
Output for 7.3.32 - 7.3.33, 7.4.33, 8.0.13
bool(false) int(48) int(48) bool(false)
Output for 7.1.25 - 7.1.30, 7.2.0 - 7.2.33
bool(false) int(48) int(48) string(10) "0x7FFFBFFF"
preferences:
146.65 ms | 408 KiB | 5 Q