std::wstring_convert::wstring_convert(3)

NAME
std::wstring_convert::wstring_convert - std::wstring_convert::wstring_convert

Synopsis
   wstring_convert() : wstring_convert( new Codecvt ) {} (1)
   explicit wstring_convert( Codecvt* pcvt ); (2)
   wstring_convert( Codecvt* pcvt, state_type state ); (3)
   explicit wstring_convert( const byte_string& byte_err,
                        const wide_string& wide_err = (4)
   wide_string() );
   wstring_convert( const std::wstring_convert& ) = delete; (5) (since C++14)
   1) Default constructor.
   2) Constructs the wstring_convert object with a specified conversion facet, using
   default-constructed values for the shift state and the error strings.
   3) Constructs the wstring_convert object with a specified conversion facet and
   specified shift state, using default-constructed values for the error strings.
   4) Constructs the wstring_convert object with specified error strings, using new
   Codecvt as the conversion facet and the default-constructed state_type as shift
   state.
   5) The copy constructor is deleted, wstring_convert is not CopyConstructible.

Parameters
   pcvt - pointer to the conversion facet of type Codecvt (behavior is undefined if
              this pointer is null)
   state - initial value of the conversion shift state
   byte_err - narrow string to display on errors
   wide_err - wide string to display on errors
   Defect reports
   The following behavior-changing defect reports were applied retroactively to
   previously published C++ standards.
     DR Applied to Behavior as published Correct behavior
   P0935R0 C++11 default constructor was explicit made implicit

Example
// Run this code
 #include <codecvt>
 #include <locale>
 #include <utility>
 // utility wrapper to adapt locale-bound facets for wstring/wbuffer convert
 template<class Facet>
 struct deletable_facet : Facet
 {
     using Facet::Facet; // inherit constructors
     ~deletable_facet() {}
 };
 int main()
 {
     // UTF-16le / UCS4 conversion
     std::wstring_convert<
         std::codecvt_utf16<char32_t, 0x10ffff, std::little_endian>
     > u16to32;
     // UTF-8 / wide string conversion with custom messages
     std::wstring_convert<std::codecvt_utf8<wchar_t>> u8towide("Error!", L"Error!");
     // GB18030 / wide string conversion facet
     typedef deletable_facet<std::codecvt_byname<wchar_t, char, std::mbstate_t>> F;
     std::wstring_convert<F> gbtowide(new F("zh_CN.gb18030"));
 }