note 103443 added to reference.pcre.pattern.modifiers

Yes. That note about needing to use the u modifier only if you want utf-8 in your pattern is not correct. Especially together with preg_replace, it becomes imperative that you use the u modifier if your subject contains UTF-8 encoded data, otherwise depending on regular expression, you will get corrupted data from the replacement operation. I just spend a few painful minutes with this <?php $in = 'éà'; $out = preg_replace('#\s+#', ' ', $in); echo "$in\n$out\n"; ?> which was echoing the original é plus a corrupted high-bit value plus a space character Reason? à is encoded as 0xc3a0 and 0xa0 is seen as whitespace matching \s if you don't provide the u-flag. Be really, really careful about this! ---- Server IP: 194.153.94.10 Probable Submitter: 77.56.160.123 ---- Manual Page -- http://www.php.net/manual/en/reference.pcre.pattern.modifiers.php Edit -- https://master.php.net/note/edit/103443 Del: integrated -- https://master.php.net/note/delete/103443/integrated Del: useless -- https://master.php.net/note/delete/103443/useless Del: bad code -- https://master.php.net/note/delete/103443/bad+code Del: spam -- https://master.php.net/note/delete/103443/spam Del: non-english -- https://master.php.net/note/delete/103443/non-english Del: in docs -- https://master.php.net/note/delete/103443/in+docs Del: other reasons-- https://master.php.net/note/delete/103443 Reject -- https://master.php.net/note/reject/103443 Search -- https://master.php.net/manage/user-notes.php