Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:79450
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Received-SPF: pass (pb1.pair.com: domain gmail.com designates 74.125.82.54 as permitted sender)
MIME-Version: 1.0
In-Reply-To: <71E539EE-AB67-46D2-826E-CE639D91BE32@ajf.me>
References: <07b6e60681651c07105d93f6af7f62f3bed9e4ed@mail.qip.ru>
	<71E539EE-AB67-46D2-826E-CE639D91BE32@ajf.me>
Date: Fri, 5 Dec 2014 20:50:15 +0100
Message-ID: <CAF+90c_UA_1PsNoQqTsnpHdKANGxxWy1Qn5C_GzNbPefFbYsFA@mail.gmail.com>
To: Andrea Faulds <ajf@ajf.me>
Cc: =?UTF-8?B?0JTQvNC40YLRgNC40Lk=?= <freax@pop3.ru>, 
	PHP internals <internals@lists.php.net>
Content-Type: multipart/alternative; boundary=089e013c6522b98c4f05097d62f6
Subject: Re: [PHP-DEV] Comparison chain
From: nikita.ppv@gmail.com (Nikita Popov)

--089e013c6522b98c4f05097d62f6
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: quoted-printable

On Fri, Dec 5, 2014 at 3:47 PM, Andrea Faulds <ajf@ajf.me> wrote:

>
> > On 5 Dec 2014, at 14:36, =D0=94=D0=BC=D0=B8=D1=82=D1=80=D0=B8=D0=B9 <fr=
eax@pop3.ru> wrote:
> >
> > Hi!
> >
> > I followed by https://wiki.php.net/rfc/howto and I would like to
> propose a concept "comparison chain" to implementing to future PHP versio=
ns.
> > It would be very usable if PHP can do that in python-style.
> >
> > Thank for your attension!
>
> Are you saying to allow (1 < x < 2) etc.? That would be nice, although
> it=E2=80=99s a backwards-compatibility break as currently (1 < x < 2) wou=
ld do
> something different, as would, say, ($x =3D=3D $y =3D=3D $z).
>

Comparisons are non-associative in PHP [1], so something like $x =3D=3D $y =
=3D=3D
$z is currently invalid code. As such this would not break compatibility.

Nikita

[1]: http://lxr.php.net/xref/PHP_TRUNK/Zend/zend_language_parser.y#81

--089e013c6522b98c4f05097d62f6--