PHP 7.4 Typed properties iteration

If you want to allow a typed attribute to be nullable you can simply add a ? before the type and give NULL as default value like that:

class DragonBallClass 
{
    public ?string $goku = NULL;
    public string $bulma = 'Bulma';
    public string $vegeta = 'Vegeta';
}

In this case NULL is a perfectly legitimate value (and not a dummy value).

demo

---

Also without using ?, you can always merge the class properties with the object properties lists:

class DragonBallClass 
{
    public string $goku;
    public string $bulma = 'Bulma';
    public string $vegeta = 'Vegeta';
}

$dragonBall = new DragonBallClass();

$classProperties = get_class_vars(get_class($dragonBall));
$objectProperties = get_object_vars($dragonBall);

var_dump(array_merge($classProperties, $objectProperties));

// array(3) {
//  ["goku"]=>
//  NULL
//  ["bulma"]=>
//  string(5) "Bulma"
//  ["vegeta"]=>
//  string(6) "Vegeta"
// }

Before we start - I think that the answer accepted by me and provided by Casimir is better and more correct than what I came up with(that also goes for the comments).

I just wanted to share my thoughts and since this is a working solution to some degree at least we can call it an answer.

This is what I came up with for my specific needs and just for fun. I was curious about what I can do to make it more the way I want it to be so don't freak out about it ;P I think that this is a quite clean workaround - I know it's not perfect though.

class MyRequest
{
    public function __construct()
    {    
        $reflectedProperties = (new \ReflectionClass($this))->getProperties();
        foreach ($reflectedProperties as $property) {
            !$property->isInitialized($this) ??
            $property->getType()->allowsNull() ? $property->setValue($this, null) : null;
        }
    }

}


class PostRequest extends MyRequest 
{
    public ?string $title;

}

$postRequest = new PostRequest();

// works fine - I have access here!
foreach($postRequest as $property) {
    var_dump($property);
}

The downfall of this solution is that you always have to make types nullable in your class. However for me and my specific needs that is totally ok. I don't mind, they would end up as nullables anyway and it might be a nice workaround for a short deadline situation if someone is in a hurry.

It still keeps the original PHP not initialized error though when the type is not nullable. I think that is actually kinda cool now. You get to keep all the things: Slim and lean classes, PHP error indicating the true nature of the problem and possibility to loop over typed properties if you agree to keep them nullable. All governed by native PHP 7 nullable operator.

Of course, this can be changed or extended to be more type-specific if that makes any sense.