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Date: Mon, 20 Aug 2012 02:36:08 -0400
Message-ID: <CAL+t6cFme5QqNY+KroQCnst4mqSuyS9oHndSQbjzysQXDW7B3g@mail.gmail.com>
To: Laruence <laruence@php.net>
Cc: Nikita Popov <nikita.ppv@gmail.com>, PHP Internals <internals@lists.php.net>
Content-Type: text/plain; charset=ISO-8859-1
Subject: Re: [PHP-DEV] [VOTE]Call for voting: support use list in foreach
From: theanomaly.is@gmail.com (Sherif Ramadan)

On Sun, Aug 19, 2012 at 2:07 AM, Laruence <laruence@php.net> wrote:
> On Sat, Aug 18, 2012 at 5:48 PM, Nikita Popov <nikita.ppv@gmail.com> wrote:
>> On Sat, Aug 18, 2012 at 6:34 AM, Laruence <laruence@php.net> wrote:
>>> Hi:
>>>     This feature introduces list() support in foreach constructs(more
>>> info can be found here: https://wiki.php.net/rfc/foreachlist).
>>>
>>>   please vote for this: https://wiki.php.net/rfc/foreachlist#vote
>>
>> Hi Lauruence!
>>
>> Is this vote just for list() or also for error suppression? I'd vote
>> +1 on the first, but -1 on the second, so it would be nice to make it
>> more clear ;)
> Hi,
>
>    okey,  I opened another vote for the foreach list with silent token
> supporting.
>
> thanks
>
>>
>> Nikita
>
>
>


Sorry, I feel like I missed the discussion phase of this RFC. I'm
unclear about how this behavior in the construct will affect existing
code. Currently, you can only use list() with arrays that have
sequential numeric keys starting from 0. So the follow does not
currently work with the list construct...

list($x, $y) = array('x'=>1, 'y'=>2); // This won't work

/* This won't work either.. at least not the way I'd expect because $y
will end up being 1 and $x will be null and an E_NOTICE level error is
thrown. */
list($x, $y) = array(1=>1, 2=>2);
var_dump($x, $y);
/*
NULL
int(1)
*/

While I see the use of the list construct as a minor improvement in
readability (it does add some syntactic sugar), I also can't imagine
that it makes things any more consistent, which is one of the points
of this RFC.

This also means that if we chose to avoid this extra level of
indirection by way of list in foreach constructs we can't expect to
access the key, which might make for another ambiguity and lead us
back to just using something like the following...

$array = array(
    'Cape Cod' => array('lat' => 12.20, 'long' => 34.60),
    'North Shore' => array('lat' => 18.72, 'long' => 4.11),
    'Mount Erie' => array('lat' => 6.02, 'long' => 21.79),
);
foreach ($array as $point => $coordinates) {
  $lat = $coordinates['lat'];
  $long = $coordinates['long'];
  echo "Coordinates for $point are: LAT = $lat, LONG = $long\n";
}

I understand we can simply say this would not be an ideal use case for
this, but then it becomes a tiny variation in syntax that only solves
a specific problem.