Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:84612
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Received-SPF: pass (pb1.pair.com: domain bof.de designates 80.242.145.70 as permitted sender)
To: internals@lists.php.net
Cc: Johannes Ott <mail@deroetzi.de>
Date: Thu, 12 Mar 2015 09:14:56 +0100
Message-ID: <6023256.6UxfYvu8RT@rofl>
User-Agent: KMail/4.14.4 (Linux/3.19.0-5.g748552c-desktop; KDE/4.14.4; x86_64; ; )
In-Reply-To: <6D.2C.32765.10EC0055@pb1.pair.com>
References: <6D.2C.32765.10EC0055@pb1.pair.com>
MIME-Version: 1.0
Content-Transfer-Encoding: quoted-printable
Content-Type: text/plain; charset="iso-8859-1"
Subject: Re: [PHP-DEV] static constructor
From: php@bof.de (Patrick Schaaf)

On Thursday 12 March 2015 00:21:34 Johannes Ott wrote:
>
> The purpose of this suggestion is to introduce a static constructor,
> which is called before the first call to class either static or
> non-static to initialize some static properties which are needed by t=
he
> class.

We are doing this in our private codebase, implemented as a feature of =
our=20
autoloader: after having loaded a class, check whether it has a static =
method=20
called 'init=A7class()', and call that.

At the moment, 63 of our 397 classes have that, so it's definitely a su=
ccess=20
for us.

One issue to think about, is whether to call that function when it's ju=
st=20
inherited. We do, and in several places, then check if (get_called_clas=
s() =3D=3D=20
__CLASS__). It's a bit tedious in places, but in other places it permit=
s=20
setting up of subclass static::$properties from a shared baseclass init=
ializer=20
method.

In principle none of that is neccessary, because one can put code outsi=
de the=20
class definition. One more line to write. In practise, it's a bit annoy=
ing, as=20
it must go after the whole class definition, or it breaks for subclasse=
s in=20
funny ways when the parent class is not already defined...

Something like your version 2 proposal, a new __magic method, would be =
my=20
prefered choice, too.

best regards
  Patrick