<?php
echo 'locale: ' . setlocale(LC_ALL, 0) . PHP_EOL;
echo preg_replace('/(*UCP)\b/', '<$0>', 'and рублей').PHP_EOL;
echo preg_replace('/(*UTF16)\b/', '<$0>', 'and рублей').PHP_EOL;
echo preg_replace('/\b/u', '<$0>', 'and рублей').PHP_EOL;
setlocale(LC_ALL, 'ru_RU.UTF-8');
echo 'locale: ' . setlocale(LC_ALL, 0) . PHP_EOL;
echo preg_replace('/(*UCP)\b/', '<$0>', 'and рублей').PHP_EOL;
echo preg_replace('/(*UTF8)\b/', '<$0>', 'and рублей').PHP_EOL;
echo preg_replace('/\b/u', '<$0>', 'and рублей').PHP_EOL;
preferences:
74.34 ms | 402 KiB | 5 Q