Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:103601
MIME-Version: 1.0
Date: Thu, 13 Dec 2018 15:04:17 +0100
Message-ID: <CAG9XoMSn7bMvKY1U56f4ybjea57Tm4XZgaz8GXQo3bN9cu2q7g@mail.gmail.com>
To: PHP Internals <internals@lists.php.net>
Content-Type: multipart/alternative; boundary="0000000000000c2aec057ce7cb1b"
Subject: Typed properties - feature request
From: benjamin.morel@gmail.com (Benjamin Morel)

--0000000000000c2aec057ce7cb1b
Content-Type: text/plain; charset="UTF-8"

Hi internals,

I have a feature request related to upcoming typed properties, that I'd
like to discuss here first.
I'm building a data mapper that will target PHP 7.4, and will make heavy
use of typed properties.

One of the features that I want to have available, is allowing to load a
partial object, by giving a list of properties to load:

$user = $userRepo->load(123, ['status', 'followerCount']);

Under the hood, load() will create a new User object using
ReflectionClass:newInstanceWithoutConstructor(), get the data from the
database and populate the requested fields using
ReflectionProperty::setValue(). Now when I do:

$userRepo->save($user);

The repo will use the new ReflectionProperty::isInitialized() method to
locate which fields are initialized, and only save these to the database.
The problem is, newInstanceWithoutConstructor() *initializes properties to
their default value*, so save() has no way to know whether initialized
properties have been explicitly set during load(), or are just default
value (note: repos are stateless).

To overcome this problem, I can think of 2 possible options:

*Option 1: add an optional parameter to
ReflectionClass::newInstanceWithoutConstructor(), to not initialize
properties to their default value:*

function newInstanceWithoutConstructor(bool $initializeProperties = true)


*Option 2: add a ReflectionProperty::unset() method:*

function unset(string $property)

This way, I could explicitly unset() every property that was not requested
during load().
Currently, there is no way to unset() a protected property from outside the
object (i.e. in the data mapper).


Note that Option 1 would have a slight performance advantage in my case,
while Option 2 may have more use cases outside of mine.

What do you think?
Cheers,
Ben

--0000000000000c2aec057ce7cb1b--