Visibility for Constants

PHP allows defining visibility for class constants.

Example

class Example {

    public const PUBLIC_CONST = "Public";
    protected const PROTECTED_CONST = "Protected";
    private const PRIVATE_CONST = "Private";

    public function show() {
        echo self::PUBLIC_CONST;
        echo self::PROTECTED_CONST;
        echo self::PRIVATE_CONST;
    }

}