Re: [RFC] Allow Reassignment of Promoted Readonly Properties in Constructor

On Mon, Feb 2, 2026, at 22:14, Nicolas Grekas wrote: > Hi Marco, > > Le lun. 2 févr. 2026 à 11:54, Marco Pivetta <ocramius@gmail.com> a écrit : >> Hey Nicolas, >> >> >> On Thu, 22 Jan 2026 at 16:34, Nicolas Grekas <nicolas.grekas+php@gmail.com >> <mailto:nicolas.grekas%2Bphp@gmail.com>> wrote: >>> Dear all, >>> >>> Here is a new RFC for you to consider: >>> ˆW; >>> Eû ” x8https://wiki.php.net/rfc/promoted_readonly_constructor_reassign >> >> >> What happens if one calls $obj->__construct(1, 2, 3) (on >> an already instantiated $obj) in the context of this patch? > > Thanks for asking, I didn't think about this. This made me also think about > ReflectionClass::newInstanceWithoutConstructor(). > I clarified this in the RFC, see "Direct __construct() Calls Cannot Bypass Readonly" > and "Reflection: Objects Created Without Constructor". > Patch and PR updated also if anyone wants to run some code where this RFC can be played with. > > Cheers, > Nicolas Hi Nicolas, Under "Child Classes Can Reassign Parent Properties": this feels like a major footgun. Calling parent::__construct() won't allow a reset (per the rules of calling a constructor directly); which would completely break inheritance... but then in the examples it says that calling a constructor directly can reset it -- but you can't? This feels really inconsistent to me. — Rob