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Date: Fri, 13 Sep 2019 09:23:45 -0400
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To: =?UTF-8?Q?Micha=C5=82_Brzuchalski?= <michal.brzuchalski@gmail.com>
Cc: PHP Internals List <internals@lists.php.net>
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Subject: Re: [PHP-DEV] [RFC] Object Initializer
From: matthewmatthew@gmail.com (Matthew Brown)

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Though this is truly a stylistic complaint, I think it will lead to
harder-to-analyse code.

Currently I have a static analysis tool that can verify (in 99% of cases)
whether all properties of a class have been initialised in the constructor.
This check is even more important in PHP 7.4, where use of a property
without instantiation is a fatal error.

Figuring out which properties have been instantiated in a constructor is
non-trivial, and it's only efficient to do it once per class.

If we adopt this into the language and people use both __construct and
object initializers for a given class, analysis would become much more
tricky.

In order to find the error in this:

abstract class A {
  public string $s;
  public int $t;
}

class B extends A {
  public bool $u;

  public function __construct() {
    $this->s =3D "hello";
  }
}

$b =3D new C {
  u =3D true
};

The analyzer needs to understand that the initialisation of B left a
property uninitialised - it warns about it in B's constructor (
https://psalm.dev/r/0e8e40fefc) but I worry that people will start to
dismiss those warnings as false-positives if this pattern becomes popular.

Best wishes,

Matt




On Thu, 12 Sep 2019 at 10:00, Micha=C5=82 Brzuchalski <
michal.brzuchalski@gmail.com> wrote:

> Hi internals,
>
> I'd like to open discussion about RFC: Object Initializer.
>
> This proposal reduces boilerplate of object instantiation and properties
> initialization in case of classes without required constructor arguments =
as
> a single expression with initializer block.
>
> https://wiki.php.net/rfc/object-initializer
>
> I appreciate any feedback you all can provide.
>
> Thanks,
> --
> Micha=C5=82 Brzuchalski
> brzuchal@php.net
>

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