====== RFC: foreach_variable supporting T_LIST ======
  * Version: 1.0
  * Date: 2011-07-06
  * Author: Xinchen Hui <laruence@php.net>
  * Status: Implemented
  * First Published at: http://wiki.php.net/rfc/foreachlist/

===== Introduction =====

This feature introduces list() support in foreach constructs:

<code php>
<?php
$users = array(
    array('Foo', 'Bar'),
    array('Baz', 'Qux'),
);

// Before
foreach ($users as $user) {
    list($firstName, $lastName) = $user;
    echo "First name: $firstName, last name: $lastName. ";
}

// After
foreach ($users as list($firstName, $lastName)) {
    echo "First name: $firstName, last name: $lastName. ";
}
</code>

This feature eliminates the use of a redundant variable ($user in the example above), reduces code verbosity in typical cases of iterating structured data, such as SQL result sets, and it doesn't introduce new keywords, but simply reuses a familiar PHP construct in a new context.

It's a commonly requested feature, and there is evidence that people already expect list() should work in this scenario:  #10203 [[https://bugs.php.net/bug.php?id=10203|allow foreach($array as list($a,$b)]]

This RFC provides a behavior specification and implementation for this feature.

===== Implementation details of the RFC =====
In order to avoid the reduce/reduce conflict, new bison rules will be added to the existing "foreach_variable", to avoid this side effect:

<code php>
<?php
foreach (array(1,3,4) as &$key => $foo) {

}
</code>

Without the new patch:
<code>
PHP Parse error:  syntax error, unexpected '&', expecting T_STRING or T_VARIABLE or '$' in /home/huixc/test.php on line 2
</code>

With the new patch:
<code>
PHP Fatal error:  Key element cannot be a reference in /home/huixc/test.php on line 2

Fatal error: Key element cannot be a reference in /home/huixc/test.php on line 2
</code>

===== Possible additional features (vote separately): silent token ======
It is possible to add support of the silent token in the new context:
<code php>
$array = array(array(1,3,4), array(1, 2));
foreach ($array as @list($a, $b, $c)) {
}                                   1
</code>

===== Patches =====
   * foreach list: https://github.com/laruence/php-src/tree/foreachlist_nosilenttoken
   * foreach list with supporting of silent token: https://github.com/laruence/php-src/tree/foreachlist
===== Vote =====
<doodle 
title="Should this RFC be merged into trunk?" auth="laruence" voteType="single" closed="true">
   * Yes
   * No
</doodle>

<doodle 
title="Should this RFC(with supporting of silent token) be merged into trunk?" auth="laruence" voteType="single" closed="true">
   * Yes
   * No
</doodle>
===== Changelog =====
  * 2011-07-06 Xinchen Hui: Initial RFC creation
  * 2011-07-06 Xinchen Hui: Updated patch
  * 2011-07-06 Xinchen Hui: Added tests phpt
  * 2011-07-07 Xinchen Hui: Added supporting for slience token(@)
  * 2011-07-07 Xinchen Hui: Updated sencode patch
  * 2011-07-08 Xinchen Hui: Added opcodes with silent token
  * 2011-07-24 Xinchen Hui: Updated patches that fixed a bug: znode->EA may be depend on an uninitialized value (thanks to Felipe)
  * 2012-07-18 Phidev: Rewrote the RFC
  * 2012-08-18 Xinchen Hui: Open voting
  * 2012-08-25 Xinchen Hui: Close voting