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