Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:46147
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Received-SPF: error (pb1.pair.com: domain lerdorf.com from 209.85.210.192 cause and error)
Message-ID: <4B082F9E.6080703@lerdorf.com>
Date: Sat, 21 Nov 2009 10:21:18 -0800
User-Agent: Thunderbird 2.0.0.23 (X11/20090817)
MIME-Version: 1.0
To: Alban <seza@paradoxal.org>
CC: internals@lists.php.net
References: <17.CC.25743.CB6770B4@pb1.pair.com>	<84B23126-8011-48DA-B65A-750AA9C5B57E@pooteeweet.org> <F9.B5.13841.B43280B4@pb1.pair.com>
In-Reply-To: <F9.B5.13841.B43280B4@pb1.pair.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Subject: Re: [PHP-DEV] suggestion about ternary operator
From: rasmus@lerdorf.com (Rasmus Lerdorf)

Alban wrote:
> Le Sat, 21 Nov 2009 09:48:10 +0100, Lukas Kahwe Smith a écrit :
> 
>> On 21.11.2009, at 06:12, Alban wrote:
>>
>>> This is not a big problem but if a solution exists, this would be so
>>> cool ! Especialy when we have to check existance of twenty or more key
>>> in array. Code would be be lighter and clear. Since i use PHP, I always
>>> have in my 'common function file' a function like that :
>>>
>>> function getIssetVar($var, $default) { return ((isset($var)) ? $var :
>>> $default); }
>>>
>>> So is it possible to make a little improvement on this operator or
>>> introduce a new operator or a core function which do that ? What's your
>>> feeling about it ?
>>
>> this feature request has already been discussed and declined:
>> http://wiki.php.net/rfc/ifsetor
>>
>> please review this rfc before continuing this thread.
>>
>> regards,
>> Lukas Kahwe Smith
>> mls@pooteeweet.org
> 
> Thanks for the link to the RFC :)
> 
> Excuse me, but I'll be little hard in this post. This for insult the 
> community but I want the community really think about the decision it 
> made and the reason why.  
> 
> I also read why it have been refused here : 
> http://www.php.net/~derick/meeting-notes.html#ifsetor-as-replacement-for-
> foo-isset-foo-foo-something-else
> 
> Is it serious ? 
> 
> «
> The name for this new operator is heavily disputed and we could not agree 
> on a decent name for it.
> »
> 
> Tomorrow I will not send food to the association for children who are 
> hungry because I can not choose between offering Thai or basmati rice.
> 
> Stop sarcasm, seriously, this is not an honorable response from people 
> making decisions. Take your responsibility and make a vote or impose a 
> name, just do it. 
> 
> « 
>   Instead of implementing ifsetor() we remove the 
>   requirement for the "middle" parameter to the ?: operator. 
> »
> 
> That's not people wants and that's not do their need.
> So that not a correct answer of the php developper demand.
> 
> « 
>   In combination with the new input_filter extension 
>   you then reach the original goal of setting a default 
>   value to a non-set input variable with:
> 
>   $blahblah = input_filter_get(GET, 'foo', FL_INT) ?: 42;
> »
> 
> I don't see how do that with the actual filter extension. Even if it is 
> possible, this is not a pretty short and easier solution than :
> 
> $var = (isset($var)) ? $var : 'default';

The ternary isn't meant to solve the isset thing you are talking about.
 It is simply a shortcut to normal ternary operations.  The most common
case where you don't know if a variable is set is on the initial input
via $_GET or $_POST and we definitely don't want people doing:

  $var = $_GET['foo'] ?: 42;

It would be an XSS disaster.  Hence the suggestion to use input_filter
there, or a similar user-supplied filtering function in which case the
ternary, as it is currently implemented, is perfectly suitable.

-Rasmus