Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:108411
MIME-Version: 1.0
References: <861afae0-4568-745f-6615-a252067cc506@aimeos.com>
 <f0c665ca-02c3-da16-bb78-30d68f6e505e@aimeos.com> <5f5a4ab3-e609-4324-b056-53f782f1a63b@www.fastmail.com>
 <d9ed2493-0273-a4b2-7ec3-9aee06457325@aimeos.com> <CALKiJKr-ZHb4sqWERe=GAWJLkp_gcqGuaZoc06nz3=VPXrxY=A@mail.gmail.com>
 <2f37a761-9a54-b8b6-3bcb-39cf2224c227@aimeos.com>
In-Reply-To: <2f37a761-9a54-b8b6-3bcb-39cf2224c227@aimeos.com>
Date: Thu, 6 Feb 2020 12:59:45 +0100
Message-ID: <CAF+90c_ZUh=YhbQUnKCLCaGOB0gE6rxQm0Fe-pA2TDEq6jGNqw@mail.gmail.com>
To: "Aimeos | Norbert Sendetzky" <norbert@aimeos.com>
Cc: Rowan Tommins <rowan.collins@gmail.com>, PHP Internals <internals@lists.php.net>
Content-Type: multipart/alternative; boundary="000000000000458287059de70339"
Subject: Re: [PHP-DEV] Re: [RFC] "arrayable" pseudo type hint
From: nikita.ppv@gmail.com (Nikita Popov)

--000000000000458287059de70339
Content-Type: text/plain; charset="UTF-8"

On Tue, Feb 4, 2020 at 7:40 PM Aimeos | Norbert Sendetzky <
norbert@aimeos.com> wrote:

> Am 04.02.20 um 19:17 schrieb Rowan Tommins:
> > I think Larry's point was that the flexibility of PHP's array type makes
> it
> > really hard to pin down whether a given object is "array-like" or not,
> and
> > which attributes a particular function actually cares about.
>
> What else besides array access, counting and traversing is possible that
> may differ from classes that implement those interfaces?
>
> > A general "intersection type" system might be more useful, because then
> you
> > could require the parts you specifically needed, such as
> > "traversable&ArrayAccess" or "traversable&countable".
>
> I think that's too complicated and we should make it as easy as possible
> for PHP developers.
>
> Also, there's already an RFC for intersection types but it was never
> adopted: https://wiki.php.net/rfc/intersection_types
>

FWIW, that's an old RFC that predates the current implementation of union
types in PHP 8 by a few years... A new proposal for intersection types
should stand a better chance now, especially as it can mostly reuse the
(relatively involved) technical underpinnings for the union types
implementation.

Nikita

--000000000000458287059de70339--