std::messages_byname(3)

NAME
std::messages_byname - std::messages_byname

Synopsis
   Defined in header <locale>
   template< class CharT >
   class messages_byname : public std::messages<CharT>;
   std::messages_byname is a std::messages facet which encapsulates retrieval of
   strings from message catalogs of the locale specified at its construction.

Specializations
   The standard library is guaranteed to provide the following specializations:
   Defined in header <locale>
   std::messages_byname<char> narrow/multibyte message catalog access
   std::messages_byname<wchar_t> wide string message catalog access

Member types
   Member type Definition
   catalog std::messages_base<CharT>::catalog
   string_type std::basic_string<CharT>

Member functions
   constructor constructs a new messages_byname facet
                 (public member function)
   destructor destroys a messages_byname facet
                 (protected member function) std::messages_byname::messages_byname
   explicit messages_byname( const char* name, std::size_t refs = 0 );
   explicit messages_byname( const std::string& name, std::size_t refs = (since C++11)
   0 );
   Constructs a new std::messages_byname facet for a locale with name.
   refs is used for resource management: if refs == 0, the implementation destroys the
   facet, when the last std::locale object holding it is destroyed. Otherwise, the
   object is not destroyed.

Parameters
   name - the name of the locale
   refs - the number of references that link to the facet std::messages_byname::~messages_byname
   protected:
   ~messages_byname();
   Destroys the facet. Inherited from std::messages

Member types
   Member type Definition
   char_type CharT
   string_type std::basic_string<CharT>

Member objects
   Member name Type
   id (static) std::locale::id

Member functions
   open invokes do_open
         (public member function of std::messages<CharT>)
   get invokes do_get
         (public member function of std::messages<CharT>)
   close invokes do_close
         (public member function of std::messages<CharT>)

Protected member functions
   do_open opens a named message catalog
   [virtual] (virtual protected member function of std::messages<CharT>)
   do_get retrieves a message from an open message catalog
   [virtual] (virtual protected member function of std::messages<CharT>)
   do_close closes a message catalog
   [virtual] (virtual protected member function of std::messages<CharT>)

Example
// Run this code
 #include <iostream>
 #include <locale>
 void try_with(const std::locale& loc)
 {
     const std::messages<char>& facet = std::use_facet<std::messages<char>>(loc);
     std::messages<char>::catalog cat = facet.open("sed", std::cout.getloc());
     if (cat < 0)
         std::cout << "Could not open \"sed\" message catalog\n";
     else
         std::cout << "\"No match\" "
                   << facet.get(cat, 0, 0, "No match") << '\n'
                   << "\"Memory exhausted\" "
                   << facet.get(cat, 0, 0, "Memory exhausted") << '\n';
     facet.close(cat);
 }
 int main()
 {
     std::locale loc("en_US.utf8");
     std::cout.imbue(loc);
     try_with(std::locale(loc, new std::messages_byname<char>("de_DE.utf8")));
     try_with(std::locale(loc, new std::messages_byname<char>("fr_FR.utf8")));
     try_with(std::locale(loc, new std::messages_byname<char>("ja_JP.utf8")));
 }

Possible output:
 "No match" Keine Übereinstimmung
 "Memory exhausted" Speicher erschöpft
 "No match" Pas de concordance
 "Memory exhausted" Mémoire épuisée
 "No match" 照合しません
 "Memory exhausted" メモリーが足りません

See also
   messages implements retrieval of strings from message catalogs
            (class template)