<?php

declare(strict_types=1);

class Test
{

    function __construct
    (
        private readonly int $id,
        public int $value,
    ) {
        # Nothing more
    }
    
    function id()
    {
        return $this->id;
    }
    
    function value(?int $value=null): int
    {
        if (is_null($value)) {
            return $this->value;
        }
        return $this->value = $value;
    }
    
}

$test = new Test(42, 255);
echo $test->id() . " = " . $test->value() . "\n";   # 42 = 255      get
echo $test->id() . " = " . $test->value(44) . "\n"; # 42 = 44       set+get
echo $test->id() . " = " . $test->value() . "\n";   # 42 = 44       get