ceph/src/boost/libs/locale/doc/faq.txt

   1 //
   2 //  Copyright (c) 2009-2011 Artyom Beilis (Tonkikh)
   3 //
   4 //  Distributed under the Boost Software License, Version 1.0. (See
   5 //  accompanying file LICENSE_1_0.txt or copy at
   6 //  http://www.boost.org/LICENSE_1_0.txt)
   7 //
   8
   9 // vim: tabstop=4 expandtab shiftwidth=4 softtabstop=4 filetype=cpp.doxygen
  10 /*!
  11 \page faq Frequently Asked Questions
  12
  13 -   \anchor faq_bad_cast <b>I try to use some Boost.Locale functions and I get an \c std::bad_cast exception thrown?</b>
  14     \n
  15     \n
  16     \b Answer: You probably try to use incorrect \c std::locale object. All Boost.Locale tools relay on \c std::locale object's facets.
  17     The locale object should be generated with \ref boost::locale::generator "generator" class and then passed to
  18     the function or alternatively global locale should be set using \c std::locale::global() function such that
  19     global locale (and default created one) would have required facets to use.
  20 -   \anchor faq_number <b>I had installed global locale and try to write something to stream but still get wrong output?</b>
  21     For example:
  22     \code
  23     #include <boost/locale.hpp>
  24     #include <iostream>
  25     int main()
  26     {
  27         boost::locale::generator gen;
  28         std::locale::global(gen(""));
  29         std::cout << boost::locale::as::date << std::time(0) << std::endl;
  30     }
  31     \endcode
  32     Prints a number instead of a date.
  33     \n
  34     \b Answer: You forget to imbue the locale to the stream. Changing the global locale does not affect the
  35     locale in existing \c iostream objects. Thus because \c std::out and other global streams were created
  36     before changing the global locale Boost.Locale manipulators have no effect. You need to write:
  37     \code
  38     #include <boost/locale.hpp>
  39     #include <iostream>
  40     int main()
  41     {
  42         boost::locale::generator gen;
  43         std::locale l = gen("");
  44         std::locale::global(l);
  45         std::cout.imbue(l);
  46         std::cout << boost::locale::as::date << std::time(0) << std::endl;
  47     }
  48     \endcode
  49
  50 */