std::wstring_convert::~wstring_convert

From cppreference.com
~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

#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