Boost.Locale
wconversions.cpp

Example of using various text conversion functions with wide strings.

//
// Copyright (c) 2009-2011 Artyom Beilis (Tonkikh)
//
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//
//
// ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !
//
// BIG FAT WARNING FOR Microsoft Visual Studio Users
//
// YOU NEED TO CONVERT THIS SOURCE FILE ENCODING TO UTF-8 WITH BOM ENCODING.
//
// Unfortunately MSVC understands that the source code is encoded as
// UTF-8 only if you add useless BOM in the beginning.
//
// So, before you compile "wide" examples with MSVC, please convert them to text
// files with BOM. There are two very simple ways to do it:
//
// 1. Open file with Notepad and save it from there. It would convert
// it to file with BOM.
// 2. In Visual Studio go File->Advances Save Options... and select
// Unicode (UTF-8 with signature) Codepage 65001
//
// Note: once converted to UTF-8 with BOM, this source code would not
// compile with other compilers, because no-one uses BOM with UTF-8 today
// because it is absolutely meaningless in context of UTF-8.
//
// ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !
//
#include <boost/locale.hpp>
#include <boost/algorithm/string/case_conv.hpp>
#include <iostream>
#include <ctime>
int main()
{
using namespace boost::locale;
using namespace std;
// Create system default locale
generator gen;
locale loc=gen("");
locale::global(loc);
wcout.imbue(loc);
// This is needed to prevent C library to
// convert strings to narrow
// instead of C++ on some platforms
std::ios_base::sync_with_stdio(false);
wcout<<L"Correct case conversion can't be done by simple, character by character conversion"<<endl;
wcout<<L"because case conversion is context sensitive and not 1-to-1 conversion"<<endl;
wcout<<L"For example:"<<endl;
wcout<<L" German grüßen correctly converted to "<<to_upper(L"grüßen")<<L", instead of incorrect "
<<boost::to_upper_copy(std::wstring(L"grüßen"))<<endl;
wcout<<L" where ß is replaced with SS"<<endl;
wcout<<L" Greek ὈΔΥΣΣΕΎΣ is correctly converted to "<<to_lower(L"ὈΔΥΣΣΕΎΣ")<<L", instead of incorrect "
<<boost::to_lower_copy(std::wstring(L"ὈΔΥΣΣΕΎΣ"))<<endl;
wcout<<L" where Σ is converted to σ or to ς, according to position in the word"<<endl;
wcout<<L"Such type of conversion just can't be done using std::toupper that work on character base, also std::toupper is "<<endl;
wcout<<L"not fully applicable when working with variable character length like in UTF-8 or UTF-16 limiting the correct "<<endl;
wcout<<L"behavoir to BMP or ASCII only"<<endl;
}
// vim: tabstop=4 expandtab shiftwidth=4 softtabstop=4
// boostinspect:noascii