<?php
$regexp = "/[а-яё]/ui";
 
// TEST
$cyrillic = 'абвгдеёжзийклмнопрстуфхцчшщъыьэюяАБВГДЕЁЖЗИЙКЛМНОПРСТУФХЦЧШЩЪЫЬЭЮЯ';
$ok = TRUE;
foreach( preg_split("//u", $cyrillic, -1, PREG_SPLIT_NO_EMPTY) AS $i => $c) {
	$test = sprintf( "ta%sle", $c);
	if( !preg_match($regexp, $test)) {
		echo "Failed on $test $i $c\n";
		$ok = FALSE;
	}
}
echo "Test " . ($ok ? "PASSED" : "FAILED") . PHP_EOL;
 

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