- var_dump: documentation ( source)
- preg_match: documentation ( source)
<?php
var_dump(strlen(𠀋));
var_dump(preg_match('//u', "\xE3\x81\x82", $matches));
var_dump(preg_match('//u', "\xF0\xA0\x80\x8B", $matches));
var_dump(preg_match('//u', "\xF0\xA0\x80\x8B\x01\xFF", $matches));
var_dump(preg_match('//u', "𠀋", $matches));
var_dump("\xF0\xA0\x80\x8B" == "𠀋");