Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:50775
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Received-SPF: error (pb1.pair.com: domain basnetworks.net from 208.97.132.202 cause and error)
DomainKey-Status: good
DomainKey-Signature: a=rsa-sha1; c=nofws; d=basnetworks.net; h=message-id
	:in-reply-to:references:date:subject:from:to:cc:mime-version
	:content-type:content-transfer-encoding; q=dns; s=
	basnetworks.net; b=MvSf5pcKypk37ZQ+tsJJmmZ//wave5lqOqM/VZWSJNkye
	gtn0fjJQ6slo7BMuBOtR0nRx8br+iCovSfJmRdg4elsACdr7VIOzamv2C+GMxHvT
	Z5kGiZM1mC2tumwESe24Ctf47aAXuGFZ56k3yw3l6yfYsTW6/5J8z6gb9YioXE=
Message-ID: <abcfef435c883db25046806037ba1624.squirrel@webmail.basnetworks.net>
In-Reply-To: <6EC3583E-E7B7-431D-B544-82135A33E351@stefan-marr.de>
References:
    <ae7aa0536c47a2ac725222d49918183f.squirrel@webmail.basnetworks.net>
    <003601cb8fd0$f6494e80$e2dbeb80$@com> <4CF3B855.5010406@sugarcrm.com>
    <003401cb8fee$1be39840$53aac8c0$@com>
    <2450924ae03481f5b1382a7f00e5743d.squirrel@webmail.basnetworks.net>
    <4CF50245.5020807@sugarcrm.com>
    <ed0a2b6089e32bc3def3c14a1f510246.squirrel@webmail.basnetworks.net>
    <4CF5118B.2030300@sugarcrm.com>
    <1faa4c3db62771335db714507ac2adfa.squirrel@webmail.basnetworks.net>
    <6EC3583E-E7B7-431D-B544-82135A33E351@stefan-marr.de>
Date: Wed, 1 Dec 2010 08:10:55 -0500
To: "Stefan Marr" <php@stefan-marr.de>
Cc: "Stas Malyshev" <smalyshev@sugarcrm.com>,
 "internals@lists.php.net" <internals@lists.php.net>
User-Agent: SquirrelMail/1.4.21
MIME-Version: 1.0
Content-Type: text/plain;charset=iso-8859-1
Content-Transfer-Encoding: quoted-printable
Subject: Re: [PHP-DEV] RFC: C-sharp style property get/set syntax for PHP
From: president@basnetworks.net

>>>> That is true for PHP variables.  isset is basically saying "does thi=
s
>>>> variable exist", and unset is saying to get rid of it.
>>>
>>> This is also true for object properties - see magic methods. I don't
>>> see
>>> why you shouldn't be able to unset them - you can do that with regula=
r
>>> properties... So what you imagine would happen if you call
>>> unset($foo->property) or isset($foo->property)?
>>
>> Its not a matter of consistency - Properties, as a cross-language
>> concept
>> are not meant to work that way.
> I tend to disagree.
> The need to be consistent inside of PHP has precedence over being
> consistent with other languages.

Unfortunately I find that to be one of the major downfalls of PHP.  It
sometimes disregards defacto standards that are set across the entire
industry, which causes a lot of frustration for new programmers.=20
Sometimes the functionality PHP adds by going its own way is worth it, bu=
t
often it is just a confusing mess.  Thats just my opinion though, YMMV.


>> You need to think of a property as a set
>> of two methods that just have a pretty syntax.  Methods cannot be unse=
t,
>> and nor should properties be allowed to.  isset() should simply tell u=
s
>> whether a property with the specified name is part of the class or not=
.
> I think, it really is the other way around.
> Properties are meant to give the programmer the illusion that she is ju=
st
> having a field.
> That is abstraction. She does not care about implementation details.
> And that is the power of properties.
>
> isset() and unset() are perfectly fine in that context.
> And I do not see a problem to provide the standard semantics for them
> automatically, and let the programmer add isset/unset methods to the
> property as needed in exactly the same style as get/set.
>
> There is a good usecase for asking whether a property has been set, for
> instance to verify initialization.
> And, of course unset has also a useful meaning. It is about the value, =
and
> even so there are methods around a value, properties are meant to be
> values.
> There are definitely use-cases where that does not hold, but that is
> application specific.
>
>
>> isset() in the way you suggest would just be confusing.  It would allo=
w
>> is
>> to say that a property does not exist, when in fact it does exist.  Th=
is
>> is not logical.
> From the docu: isset =97 Determine if a variable is set and is not NULL
> There is nothing confusing about isset($this->Hours) =3D=3D FALSE in yo=
ur
> example if isset($this->seconds) =3D=3D FALSE.

Right, I understand how it would work, and the reasons why it would "make
sense", but it just feels wrong to me.  When you unset() a variable in a
class, that whole variable is gone.  Its not just hiding somewhere, its
completely gone.  If a property were to "pretend" it is not set, with an
isset method, it would still be there - just hiding.  That is why it does
not make sense to me.

- Dennis