====== PHP RFC: grapheme_strrev: strrev for grapheme cluster ======
  * Version: 0.9
  * Date: 2026-01-14
  * Author: Yuya Hamada <youkidearitai@gmail.com>
  * Status: Under Discussion
  * Implementation: https://github.com/php/php-src/pull/20949



===== Introduction =====

This proposal is strrev for grapheme cluster unit function. Userland sometimes shows [[https://github.com/search?q=mb_strrev&type=code|mb_strrev]] function, but mbstring(Unicode code point unit) can not support multi code point (for example, emoji etc...).

Almost same of Swift's [[https://developer.apple.com/documentation/swift/string/reversed()|String.reversed()]].


===== Proposal =====
Add grapheme_strrev function.

<PHP>
<?php
echo grapheme_strrev("αあいうえお👨‍👨‍👧‍👦"); // result is "👨‍👨‍👧‍👦おえういあα"
echo grapheme_strrev("ﻡﺮﺤﺑًﺍ"); // result is "ﺍً ﺐﺣﺮﻣ" (Hello in Arabic, Also works RtoL languages)
?>
</PHP>



===== Backward Incompatible Changes =====

This could break a function existing in userland with the same name.


===== Proposed PHP Version(s) =====

Next of PHP 8.5 (PHP 8.6 or PHP 9.0)

===== RFC Impact =====
==== To the Ecosystem ====
None

==== To Existing Extensions ====
Adds grapheme_strrev() to the intl extension.

==== To SAPIs ====
None

===== Open Issues =====
None

===== Future Scope =====
None


===== Voting Choices =====
Pick a title that reflects the concrete choice people will vote on. 

Please consult [[https://github.com/php/policies/blob/main/feature-proposals.rst#voting-phase|the php/policies repository]] for the current voting guidelines.

----

Primary Vote requiring a 2/3 majority to accept the RFC:

<doodle title="Add grapheme_strrev function" voteType="single" closed="true" closeon="2025-01-01T15:30:00Z">
   * Yes
   * No
   * Abstain
</doodle>

===== Patches and Tests =====

  * https://github.com/php/php-src/pull/20949

===== Implementation =====
After the RFC is implemented, this section should contain:
  - the version(s) it was merged into
  - a link to the git commit(s)
  - a link to the PHP manual entry for the feature

===== References =====
  * https://news-web.php.net/php.internals/129765

===== Rejected Features =====
Keep this updated with features that were discussed on the mail lists.

===== Changelog =====
If there are major changes to the initial proposal, please include a short summary with a date or a link to the mailing list announcement here, as not everyone has access to the wikis' version history.