<?php
class Example
{
    public private(set) static string $classTitle = 'Example class';

    // Implicitly public-read, just like object properties.
    protected(set) static int $counter = 0;

    public static function changeName(string $name): void
    {
        // From private scope, so this is allowed.
        self::$classTitle = $name;
    }
}

print Example::$classTitle; // Allowed.

Example::$classTitle = 'Nope'; // Disallowed.
?>