//  locale_info.cpp  ---------------------------------------------------------//

//  Copyright Beman Dawes 2011

//  Distributed under the Boost Software License, Version 1.0.
//  See http://www.boost.org/LICENSE_1_0.txt

#include <locale>
#include <iostream>
#include <exception>
#include <cstdlib>
using namespace std;

#ifdef _MSC_VER
#pragma warning(push)
#pragma warning(disable : 4996) // ... Function call with parameters that may be unsafe
#endif

namespace {
void facet_info(const locale& loc, const char* msg)
{
    cout << "has_facet<std::codecvt<wchar_t, char, std::mbstate_t> >("
         << msg << ") is "
         << (has_facet< std::codecvt< wchar_t, char, std::mbstate_t > >(loc) ? "true\n" : "false\n");
}

void default_info()
{
    try
    {
        locale loc;
        cout << "\nlocale default construction OK" << endl;
        facet_info(loc, "locale()");
    }
    catch (const exception& ex)
    {
        cout << "\nlocale default construction threw: " << ex.what() << endl;
    }
}

void null_string_info()
{
    try
    {
        locale loc("");
        cout << "\nlocale(\"\") construction OK" << endl;
        facet_info(loc, "locale(\"\")");
    }
    catch (const exception& ex)
    {
        cout << "\nlocale(\"\") construction threw: " << ex.what() << endl;
    }
}

void classic_info()
{
    try
    {
        locale loc(locale::classic());
        cout << "\nlocale(locale::classic()) copy construction OK" << endl;
        facet_info(loc, "locale::classic()");
    }
    catch (const exception& ex)
    {
        cout << "\nlocale(locale::clasic()) copy construction threw: " << ex.what() << endl;
    }
}
} // namespace

int main()
{
    const char* lang = getenv("LANG");
    cout << "\nLANG environmental variable is "
         << (lang ? lang : "not present") << endl;

    default_info();
    null_string_info();
    classic_info();

    return 0;
}

#ifdef _MSC_VER
#pragma warning(pop)
#endif
