PHP RFC: grapheme_strrev: strrev for grapheme cluster

• Version: 0.9
• Date: 2026-01-14
• Author: Yuya Hamada youkidearitai@gmail.com
• Status: Draft
• Implementation: TBD https://github.com/...

This proposal is strrev for grapheme cluster unit function. User land sometimes shows mb_strrev function, but mbstring(Unicode code point unit) can not support multi code point (for example, emoji etc...).

Almost same of Swift's String.reversed().

Add grapheme_strrev function.

<?php
 
echo grapheme_strrev("αあいうえお👨‍👨‍👧‍👦"); // result is "👨‍👨‍👧‍👦おえういあα"
 
?>

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

Next of PHP 8.5 (PHP 8.6 or PHP 9.0)

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