Re: [Boost-users] [Locale] inconsistent results for utf-8 collation

----- Original Message -----

From: Patrick Ohly To: boost-users@lists.boost.org Cc: Sent: Wednesday, August 29, 2012 10:27 AM Subject: [Boost-users] [Locale] inconsistent results for utf-8 collation

Hello!

When comparing the following UTF-8 string pairs using Boost.Locale (any backend) at the "identical" level (accents are relevant) and a UTF-8 locale (I tried de_DE.utf-8) on Debian Testing (boost 1.49), I get a result that does not make sense to me.

"Muller" is considered less than "Müller" (as expected), but "Muller 2" is considered more than "Müller 1", despite the different result for the names alone.

Do I have bug in my code, in the underlying libraries or in my expectations?

Collations != Lexicographical Comparison. It is not a mistake that you get the same results for all backends: icu, posix and std. Take even OS C API strcoll you'll see the same behavior (for the reason) The point is that the difference between "B" and "A" is more important than the difference between "ü" and "u" i.e. it first sorts "Muller B" and "Müller A" without accents and than sorts if identical according to the accents. Artyom Beilis -------------- CppCMS - C++ Web Framework:   http://cppcms.com/ CppDB - C++ SQL Connectivity: http://cppcms.com/sql/cppdb/