3v4l.org

run code in 300+ PHP versions simultaneously
<?php $pattern = '/^([a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*[\/\\\\]?)*[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*$/D'; $class = ' Foo'; var_dump(preg_match($pattern, $class));
Output for 5.6.0 - 5.6.26, 7.0.0 - 7.0.20, 7.1.0 - 7.1.7, 7.2.0 - 7.2.33, 7.3.16 - 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
int(0)

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150.07 ms | 403 KiB | 180 Q