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@ 2025-06-04T19:39:44Z

<?php
class Bar {
    public function __construct(
        public Bar $bar,
        public int $x,
        public bool $main = false,
    ) {}

    public function withMain(): self
    {
        $clone = clone $this;
        $clone->main = true;

        return $clone;
    }
}

class Fiz {
    public Bar|null $cache = null;

    public function foo(int $i)
    {
        if (!$this->cache) {
            $this->cache = $this->factor($i);
        }

        if ($i <= 1) {
            return $this
                ->cache
                ->withMain();
        }

        return $this->cache;
    }

    public function factor(int $i): object
    {
        $reflector = new ReflectionClass(Bar::class);

        return $reflector->newLazyGhost(
            function (Bar $bar) use ($i) {
                $bar->__construct($this->foo($i + 1), 2);
            },
        );
    }
}

$fiz = new Fiz();

$f = $fiz->foo(0);
var_dump($f->bar->bar->x);

Output for 8.4.1 - 8.4.14: Fatal error: Uncaught Error: Typed property Bar::$bar must not be accessed before initialization in /in/lYpu1:51 Stack trace: #0 {main} thrown in /in/lYpu1 on line 51
Process exited with code 255.
Output for 8.2.0 - 8.2.29, 8.3.0 - 8.3.26: Fatal error: Uncaught Error: Call to undefined method ReflectionClass::newLazyGhost() in /in/lYpu1:40 Stack trace: #0 /in/lYpu1(24): Fiz->factor(0) #1 /in/lYpu1(50): Fiz->foo(0) #2 {main} thrown in /in/lYpu1 on line 40
Process exited with code 255.

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