<?php
class Example {
    public function __construct(public int $data) {
        echo __METHOD__, "\n";
    }
}

$initializer = static function (Example $ghost): void {
    // Initialize
    $ghost->__construct(1);
};

$reflector = new ReflectionClass(Example::class);
$object = $reflector->newLazyGhost($initializer);

var_dump($object);
var_dump($object instanceof Example);

// Triggers initialization, and fetches the property after that
var_dump($object->data);