std::wstring_convert<Codecvt,Elem,Wide_alloc,Byte_alloc>::~wstring_convert (3) - Linux Manuals

std::wstring_convert<Codecvt,Elem,Wide_alloc,Byte_alloc>::~wstring_convert: std::wstring_convert<Codecvt,Elem,Wide_alloc,Byte_alloc>::~wstring_convert


std::wstring_convert<Codecvt,Elem,Wide_alloc,Byte_alloc>::~wstring_convert - std::wstring_convert<Codecvt,Elem,Wide_alloc,Byte_alloc>::~wstring_convert



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


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


// 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