Question

Assume we have some object

$a = new stdClass;
$a->b = 7;
$a->c = 'o';
$a->d = array(1,2,3);

Also we have a function which doing something with some of properties of our object (for example b and d[1]).

My question: Should my function accept whole object as a parameter like:

function some($a) {
 var_dump($a->b);
 var_dump($a->d[1]);
}

some($a);

or accept only certain fields which it’s process like:

function some($b, $d) {
 var_dump($b);
 var_dump($d);
}

some($a->b, $a->d[1]);

Actually no matter is $a object or array.

Answer 1

I believe the first option is the way to go.

function some($a) {
 var_dump($a->b);
 var_dump($a->d[1]);
}

some($a);

Because maybe over time you will need other parts of that object/array and you will have to modify the function and the calls where you make them.
So function some() can be a global function and used in other ways, you can add later statements, modify the function without having to modify everywhere.

function some($a, $param1 = 1){
    if($param1 == 1){
        var_dump($a->c);
        var_dump($a->d[2]);
    } else {
        var_dump($a->b);
        var_dump($a->d[1]);
    }
}