std::wstring_convert::~wstring_convert

 

C++

Language

Standard Library Headers

Freestanding and hosted implementations

Named requirements

Language support library

Concepts library (C++20)

Diagnostics library

Utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Input/output library

Localizations library

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Filesystem library (C++17)

Technical Specifications

 

Localizations library

Locales and facets
locale
use_facet	has_facet
Character classification
isspace isblank (C++11) iscntrl isupper islower isalpha	isdigit ispunct isxdigit isalnum isprint isgraph
Conversions
toupper tolower	wstring_convert (C++11) wbuffer_convert (C++11)
Facet category base classes
ctype_base codecvt_base messages_base	time_base money_base
Facet categories
ctype ctype<char> codecvt collate messages time_get time_put	num_get num_put numpunct money_get money_put moneypunct
Locale-specific facets
ctype_byname codecvt_byname messages_byname collate_byname	time_get_byname time_put_byname numpunct_byname moneypunct_byname
Code conversion facets
codecvt_utf8 (C++11) codecvt_utf16 (C++11)	codecvt_utf8_utf16 (C++11) codecvt_mode (C++11)
C locale
setlocale localeconv lconv	LC_ALLLC_COLLATELC_CTYPELC_MONETARYLC_NUMERICLC_TIME

 

std::wstring_convert

Member functions

wstring_convert::wstring_convert

wstring_convert::~wstring_convert

wstring_convert::from_bytes

wstring_convert::to_bytes

wstring_convert::converted

wstring_convert::state

 

~wstring_convert();

Destroys the wstring_convert object and deletes the pointer to the conversion facet.

Notes

Some implementations are able to delete any facet, including the locale-specific facets with protected destructors. Other implementations require the facet to have a public destructor, similar to the the locale-independent facets from <codecvt>. This is LWG issue 721

Example

Run this code

#include <locale>
#include <utility>
#include <codecvt>
 
// utility wrapper to adapt locale-bound facets for wstring/wbuffer convert
template<class Facet>
struct deletable_facet : Facet
{
    template<class ...Args>
    deletable_facet(Args&& ...args) : Facet(std::forward<Args>(args)...) {}
    ~deletable_facet() {}
};
 
int main()
{
    // GB18030 / UCS4 conversion, using locale-based facet directly
    // typedef std::codecvt_byname<char32_t, char, std::mbstate_t> gbfacet_t;
    // Compiler error: "calling a protected destructor of codecvt_byname<> in ~wstring_convert"
    // std::wstring_convert<gbfacet_t> gbto32(new gbfacet_t("zh_CN.gb18030"));
 
    // GB18030 / UCS4 conversion facet using a facet with public destructor
    typedef deletable_facet<std::codecvt_byname<char32_t, char, std::mbstate_t>> gbfacet_t;
    std::wstring_convert<gbfacet_t> gbto32(new gbfacet_t("zh_CN.gb18030"));
} // destructor called here