====== PHP RFC: array_reindex function ======
  * Version: 0.1
  * Date: 2019-03-07
  * Author: Andrey Gromov, andrewgrom@rambler.ru
  * Status: Draft
  * First Published at: http://wiki.php.net/rfc/array_reindex

===== Introduction =====
It is not rare case when we need only values from some array. Usually we use constructs like: <code=php>$array = array_values($array);</code>
In fact I see many code like <code=php>$new_array = array_values($array);</code> without any usage of $array after this line. 

Also, common case is skip null or empty values from this resulting array, then we use <code=php>if(empty($value)) continue;</code> inside loop.

In those cases array_values create redundant structures, and ifs slow down execution and raise complexity of code.

===== Proposal =====
I propose to add new "array_reindex" function into standard library. This function will receive array by reference, optionally remove useless values and make in-place conversion to packed array.

<code=php>array_reindex ( array &$array [, int $flags = ARRAY_REINDEX_NO_SKIP ] ) : bool</code>

Where $flags is bitmask of filtering constants.

If array is kept unchanged then returns FALSE, otherwise returns TRUE.

===== Backward Incompatible Changes =====
Only if the same function declared inside user code.

===== Proposed PHP Version(s) =====
Next PHP 7.x or PHP 8.

==== New Constants ====
<code=php>ARRAY_REINDEX_NO_SKIP = 1<<0; // Keep all values
ARRAY_REINDEX_SKIP_NULL = 1<<1; // Skip NULL values
const ARRAY_REINDEX_SKIP_EMPTY = 1<<2; //Skip empty(false) values</code>

In current realisation it is possible to use all constant simultaneously and only most greedly will be used.

===== Future Scope =====
Maybe extend filtering scope.

===== Patches and Tests =====
I will write tests after(if) I receive green light. :)

===== Implementation =====
Review is needed. I not sure if my code does not have any problems.
https://github.com/php/php-src/compare/master...rjhdby:array_reindex

===== References =====

===== Rejected Features =====