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Date: Fri, 18 Jul 2025 19:54:45 +0200
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Subject: Re: [PHP-DEV] [RFC] Readonly property hooks
To: Rob Landers <rob@bottled.codes>, Larry Garfield <larry@garfieldtech.com>,
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From: tim@bastelstu.be (=?UTF-8?Q?Tim_D=C3=BCsterhus?=)

Hi

On 7/18/25 17:49, Rob Landers wrote:
> Wasn’t that the entire point of readonly classes? Because it was painful to write readonly for every property.

It was certainly *one point*, but not the *entire* point. Quoting from 
the RFC (https://wiki.php.net/rfc/readonly_classes):

"it's still not easy to declare (quasi-)immutable classes"

and then further:

"it will prevent the creation of dynamic properties"

and

"a readonly class can only extend a readonly parent"

So the point of the RFC is not "adding readonly for every property is 
verbose", but "I want to be able to define immutable classes", which, as 
I outlined before, is something different.

> The behavior of the class doesn’t magically change. Or, at least, I hope it doesn’t.

The behavior of the class changes, since dynamic properties will now be 
legal. It also breaks any child classes, since child classes of 
non-readonly classes may not be readonly (not even if all properties are 
already readonly). The behavior doesn't change magically, though, it 
changes due to the intentional removal of the `readonly` keyword on the 
class.

> Unless I missed something. Hooks are fancy methods? There is nothing intrinsic about object properties. There is nothing that says two calls to the same property’s getters are going to result in the same values. There is asynchronous php, declare ticks, etc. especially in the case of globals, there is no guarantee you even have the same object. At the end of the day, it is up to the programmer building that system / program to provide those guarantees— not the language.

I agree with both Eric's response to this paragraph.

Best regards
Tim Düsterhus