Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:37323
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Received-SPF: error (pb1.pair.com: domain interjinn.com from 66.11.173.122 cause and error)
To: Nathan Nobbe <quickshiftin@gmail.com>
Cc: RQuadling@googlemail.com,
	"John Carter -X (johncart - PolicyApp Ltd at Cisco)" <johncart@cisco.com>,
	internals@lists.php.net
In-Reply-To: <7dd2dc0b0804292051o4fd5e77eu6f8faecad93c378a@mail.gmail.com>
References: <48169695.9040803@omegavortex.net>
	 <BADE85FDE9053E4AAEC411E40C77C2911A6693@xmb-ams-33e.emea.cisco.com>
	 <fv6sgn$676$1@ger.gmane.org>
	 <27A086AB-E111-49C1-ABBD-28FB6E1677BD@procata.com>
	 <48175A65.4070301@zend.com>
	 <BADE85FDE9053E4AAEC411E40C77C2911A697B@xmb-ams-33e.emea.cisco.com>
	 <1209512914.7057.296.camel@blobule>
	 <10845a340804291714g7eb10362m17af4abecbadf0e4@mail.gmail.com>
	 <7dd2dc0b0804291801m627a7c31h8dd796d7fa1d1257@mail.gmail.com>
	 <1209518549.7057.313.camel@blobule>
	 <7dd2dc0b0804292051o4fd5e77eu6f8faecad93c378a@mail.gmail.com>
Content-Type: text/plain
Organization: InterJinn
Date: Wed, 30 Apr 2008 00:05:38 -0400
Message-ID: <1209528338.7057.349.camel@blobule>
Mime-Version: 1.0
Content-Transfer-Encoding: 7bit
Subject: Re: [PHP-DEV] Class Properties in Interfaces?
From: robert@interjinn.com (Robert Cummings)

On Tue, 2008-04-29 at 23:51 -0400, Nathan Nobbe wrote:
> On Tue, Apr 29, 2008 at 9:22 PM, Robert Cummings <robert@interjinn.com>
> wrote:
> 
> >
> > That should be a matter of choice for the developer. When you say
> "but
> > when, down the road, some logic...", all I see is you waving your
> hands
> > in the air and presuming that the logic will change. The logic may
> not
> > change, in which case why am I incurring the cost of getter/setter
> > methods. "If" the logic changes, I'll be happy to add getter and
> setter
> > methods at that time and punt the needed functionality into the
> magic
> > methods which will call the appropriate getter or setter method. You
> are
> > preparing for a future that may not come, I am willing to
> retroactively
> > handle that future "if" it arrives. Neither approach strikes me as
> being
> > more correct but rather they each presume an educated guess on the
> > likelihood of the property changing it's semantics down the road.
> 
> 
> the developer does have a choice.  to use an interface, or an abstract
> class.  data facilitates methods accomplishing what it is they
> purport.
> quite frankly, i have never written an interface with getters and / or
> setters anyway, nor do i see the need to.  i would consider it silly.
> interfaces are typically used to say, any class that makes this happen
> will
> likely do it in a way differently than all the others.  since, getters
> and
> setters are almost always implemented the exact same way i find these
> topics
> to be rather different.  if there is in fact a standard way of doing
> things
> for any given interface, then to realize it, a common implementor
> class can
> be composed, and delegated to by classes that implement said interface
> in
> the 'standard' way.

Abstract classes and interfaces are not the same. They are used for
fundamentally different reasons. An interface is to enforce a contract
for all implementations of the interface. Therefore if I were to create
an interface with an interface property of x, then all implementations
using that interface would know that property x exists and could use it
thusly without having to check for it's existence. Using an abstract
class is a hack, it's not sufficient for enforcement, and you can't
combine multiple abstract classes as you can with interfaces.

Cheers,
Rob.
-- 
http://www.interjinn.com
Application and Templating Framework for PHP