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run code in 150+ php & hhvm versions
Bugs & Features
<?php setlocale(LC_ALL, 'ru_RU.cp1251'); echo preg_replace ('/\PL/iu', '_', 'ёйцукенгшщзхъфывапролджэячсмитьбю');
Output for 4.4.0 - 4.4.9, 5.0.5 - 5.6.28, hhvm-3.10.0 - 3.12.0, 7.0.0 - 7.1.0
ёйцукенгшщзхъфывапролджэячсмитьбю
Output for 4.3.11, 5.0.0 - 5.0.4
Warning: preg_replace(): Compilation failed: PCRE does not support \L, \l, \N, \P, \p, \U, \u, or \X at offset 1 in /in/rfItI on line 3
Output for 4.3.0 - 4.3.10
Warning: Compilation failed: PCRE does not support \L, \l, \N, \P, \p, \U, \u, or \X at offset 1 in /in/rfItI on line 3