Static code analysis maestro @ Exakat # PHP expert elePHPant breeder. https:// linktr.ee/exakat
Enumerations are backed by strings, they work with in_array(), but not with array_unique()
Well, at least, not directly.
Also, did you know Enum::cases() ?
https://php-tips.readthedocs.io/en/latest/tips/array_unique_and_enum.html