Enumeration static methods

Enumerations may also have static methods. The use for static methods on the enumeration itself is primarily for alternative constructors. E.g.:

<?php

enum Size
{
    case Small;
    case Medium;
    case Large;

    public static function fromLength(int $cm): static
    {
        return match(true) {
            $cm < 50 => static::Small,
            $cm < 100 => static::Medium,
            default => static::Large,
        };
    }
}
?>

Static methods may be public, private, or protected, although in practice private and protected are equivalent as inheritance is not allowed.