std::messages_byname

 

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Localization library

Locales and facets   Locales has_facet use_facet locale Facet category base classes ctype_base codecvt_base messages_base time_base money_base ctype facets ctype ctype<char> ctype_byname codecvt codecvt_byname numeric facets num_get num_put numpunct numpunct_byname collate facets collate collate_byname time facets time_get time_put time_get_byname time_put_byname

monetary facets money_get money_put moneypunct moneypunct_byname messages facets messages messages_byname Character classification and conversion Character classification isspace    iscntrl isupper islower    isalpha ispunct isdigit    isxdigit isalnum isblank (C++11) isprint isgraph Character conversions toupper    tolower String and stream conversions wstring_convert (C++11)(until C++26) wbuffer_convert (C++11)(until C++26) Unicode conversion facets codecvt_utf8 (C++11)(until C++26) codecvt_utf16 (C++11)(until C++26) codecvt_utf8_utf16 (C++11)(until C++26) codecvt_mode (C++11)(until C++26) C library locales LC_ALLLC_COLLATELC_CTYPELC_MONETARYLC_NUMERICLC_TIME    setlocale localeconv lconv

 

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

Nested types

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 = 0 );		(since C++11)

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

Nested types

Type	Definition
char_type	CharT
string_type	std::basic_string<CharT>

Data members

Member	Description
std::locale::id id [static]	the identifier of the facet

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

Inherited from std::messages_base

Nested types

Type	Definition
catalog	an unspecified signed integer type

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)