Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:52088
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Received-SPF: pass (pb1.pair.com: domain gmail.com designates 209.85.213.42 as permitted sender)
DomainKey-Status: bad
DomainKey-Signature: a=rsa-sha1; c=nofws;
        d=gmail.com; s=gamma;
        h=mime-version:in-reply-to:references:date:message-id:subject:from:to
         :cc:content-type;
        b=hVapV6i7Wt5FlT39/afkg0LmBI6cw9YfadNcwvRJeVaj8FvkdYZoiULszMFQ2VmOPU
         8p/J1Edj1haau33kRbCMIOrDPs/dulipgnB+dtq5OelhyDnAmUUm8qieybZcfpvYeDPI
         bmeXqvyt8n9ShWMp0Fx9z99gF7zavGsZIUGa8=
MIME-Version: 1.0
In-Reply-To: <BANLkTi=fzZtCRf5xDxaNa3QYO4y=pfxVjA@mail.gmail.com>
References: <AANLkTimDdM4Udx53qW8jU4NuP3kU8+vmU6y4ZgXRVn+X@mail.gmail.com>
	<BANLkTinMW_iqqOPJCuLnCB+-VEKxapPdGg@mail.gmail.com>
	<4DB923E6.3020307@sugarcrm.com>
	<BANLkTi=4FzRJuYpK3C_ZD=JYZq2xq6hzJw@mail.gmail.com>
	<4DB9A7BE.6010307@sugarcrm.com>
	<BANLkTinB6rbzxWRJzyp1Nr+eLh8TO3tfFg@mail.gmail.com>
	<1304016828.1561.103.camel@guybrush>
	<BANLkTi=DtBC5sDEWASXmfWA3Ovqf4rvAbg@mail.gmail.com>
	<BANLkTimF0qXzJCTfJhCYtUe6-Gf29_TxSA@mail.gmail.com>
	<BANLkTi=fzZtCRf5xDxaNa3QYO4y=pfxVjA@mail.gmail.com>
Date: Fri, 29 Apr 2011 20:04:24 +0200
Message-ID: <BANLkTinFUCsf6LZAEK4MQFU4in1AmpGoDA@mail.gmail.com>
To: Martin Scotta <martinscotta@gmail.com>
Cc: =?UTF-8?Q?Johannes_Schl=C3=BCter?= <johannes@schlueters.de>, 
	internals <internals@lists.php.net>, Felipe Pena <felipensp@gmail.com>, 
	Stas Malyshev <smalyshev@sugarcrm.com>, Ferenc Kovacs <info@tyrael.hu>
Content-Type: multipart/alternative; boundary=0016367657e013f65c04a2128126
Subject: Re: [PHP-DEV] [RFC] Return type-hint
From: peter.e.lind@gmail.com (Peter Lind)

--0016367657e013f65c04a2128126
Content-Type: text/plain; charset=UTF-8

On Apr 29, 2011 4:47 PM, "Martin Scotta" <martinscotta@gmail.com> wrote:
>
>
>  Martin Scotta
>
>
> On Thu, Apr 28, 2011 at 5:15 PM, Peter Lind <peter.e.lind@gmail.com>
wrote:
>>
>> 2011/4/28 Martin Scotta <martinscotta@gmail.com>:
>>
>> * snip *
>>
>> > IMHO I would not trust on any return value, as PHP did not ensure
anything
>> > about them.
>> > Even more, I do not write code that depend on return values, I prefer
to
>> > use input/output parameters,
>>
>> I cannot help but wonder why PHP is your language of choice. I mean no
>> disrespect, but PHP does not have strict typing (for a reason) and
>> forcing it upon PHP seems strange to me. Seeing as a) you'll either
>> have to implement the return type hinting yourself in which case you'd
>> know anyway what the return value is or b) you'd have to have others
>> implement it in their libraries in which case you'd have to wait years
>> for any noticeable effect, the feature seems useful only in edge cases
>> (such as Hiphop, which I think one can question the mainstream
>> usefulness of, currently).
>
>
> I understand why PHP does not have strict typing as much as I understand
why PHP do not have good-qualities third-party libraries.
> I'm not saying that there aren't good libraries, but the language has many
holes that makes almost impossible to build solid library (ie: include)

I have come across good php libraries. In fact, I haven't used ant really
bad ones. Again, maybe its a question of different environments - but I
cannot see any reason why building a library should be inherently harder in
php than strictly-typed languages.

> All the strictness of ppp, typehint and the like are not restrict things,
they are meant as boundaries for client code, to ensure the correct and well
defined behavior.

There's a very big difference between ppp and typehinting. As Stas noted,
they serve very different purposes - and while ppp typically goes with oop
(though not in every language), strict typing is not in any way necessary to
do oop. That should be obvious given the large amount of working oop code
out there.

> It's ok if you write all you code as procedural, or you don't like to
write classes, but IMHO the language should provide a solid foundation for
them, this way you can rely on libraries for common task and make your
procedural code even simpler, shorter and safer.

My background was assembler before languages like php. To me, strict typing
makes it harder, not easier, to make or use a good library. That's not to
say that strict typing is bad - just that what you need depends on your
experience. I've never had a need for strict typing in php, I don't find
myself making the errors that strict typing solves in, say c#.

> I'm not sure if return typehint will be a good idea, but I'm not against
it.
> I believe the language has to deal with other "pending" stuff prior to
this. PHP has many blind areas, whenever you call something, you don't know
if you will return or it will just die in a non-sense Fatal error.

Honestly, I've never had this problem, and I'd like to hear mire of your dev
environment to see what leads to them :)

Regards
Peter

>>
>> Personally, I read code if I'm not sure what a given function/method
>> will return - or just test. I actually thought unit tests took care of
>> issues like this. I don't think having a list of possible return
>> values would make things simpler than the good old "try it and see" -
>> which is one of the greatest assets of PHP.
>>
>> > This is the safer way I've found to achieve the same behavior
>> >
>> > function no_return(ReturnStatus $returnStatus) {
>> >   doSomething();
>> >
>> >   if ( itWasOk() )
>> >   {
>> >       $returnStatus->setReturnValue( new Foo ); // return type hint
>> >       $returnStatus->success(); // return status
>> >   }
>> >   elseif ( isWasCritical() )
>> >   {
>> >       $returnStatus->setException( new RuntimeException );
>> >       $returnStatus->exception(); // return status
>> >   }
>> >   else
>> >   {
>> >       $returnStatus->fail(); // return status
>> >   }
>> > }
>> >
>> > Of course I don't write all functions like this.
>> > This is pattern I use when I need to ensure that the type returned is
valid.
>>
>> I just return what I need to from the function/method or throw an
>> exception. Indicating that you want to throw an exception instead of
>> actually throwing one seems ... overly polite, at best. As far as I
>> can tell, you'd have to check the ReturnStatus object anyway, so I
>> don't see how you're any safer (PHP has functions for checking null
>> values, false values, try/catch blocks and other things too). But
>> maybe we're dealing with very different development environments and I
>> just cannot see the usefulness of the suggested as it wouldn't make a
>> positive difference in mine.
>>
>> Just a perspective from a typical webdev.
>> Regards
>> Peter
>>
>> --
>> <hype>
>> WWW: plphp.dk / plind.dk
>> LinkedIn: plind
>> BeWelcome/Couchsurfing: Fake51
>> Twitter: kafe15
>> </hype>
>
>

--0016367657e013f65c04a2128126--