std::wbuffer_convert<Codecvt,Elem,Tr>::wbuffer_convert (3) - Linux Man Pages

std::wbuffer_convert<Codecvt,Elem,Tr>::wbuffer_convert: std::wbuffer_convert<Codecvt,Elem,Tr>::wbuffer_convert

NAME

std::wbuffer_convert<Codecvt,Elem,Tr>::wbuffer_convert - std::wbuffer_convert<Codecvt,Elem,Tr>::wbuffer_convert

Synopsis


wbuffer_convert() : wbuffer_convert(nullptr) { } (1)
explicit wbuffer_convert( std::streambuf* bytebuf,
Codecvt* pcvt = new Codecvt, (2)
state_type state = state_type() );
wbuffer_convert(const std::wbuffer_convert&) = delete; (3) (since C++14)


1) Default constructor.
2) Constructs the wbuffer_convert object with the specified underlying byte stream, specified codecvt facet, and specified initial conversion state (all parameters are optional)
3) The copy constructor is deleted, wbuffer_convert is not CopyConstructible

Parameters


bytebuf - pointer to std::streambuf to serve as the underlying narrow character stream
pcvt - pointer to a standalone (not managed by a locale) std::codecvt facet. The behavior is undefined if this pointer is null.
state - the initial value of the character conversion state


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 <iostream>
  #include <sstream>
  #include <locale>
  #include <codecvt>
  int main()
  {
      // wrap a UTF-8 string stream in a UCS4 wbuffer_convert
      std::stringbuf utf8buf(u8"z\u00df\u6c34\U0001f34c"); // or u8"zß水🍌"
                         // or "\x7a\xc3\x9f\xe6\xb0\xb4\xf0\x9f\x8d\x8c";
      std::wbuffer_convert<std::codecvt_utf8<wchar_t>> conv_in(&utf8buf);
      std::wistream ucsbuf(&conv_in);
      std::cout << "Reading from a UTF-8 stringbuf via wbuffer_convert:\n";
      for(wchar_t c; ucsbuf.get(c); )
          std::cout << std::hex << std::showbase << c << '\n';


      // wrap a UTF-8 aware std::cout in a UCS4 wbuffer_convert to output UCS4
      std::wbuffer_convert<std::codecvt_utf8<wchar_t>> conv_out(std::cout.rdbuf());
      std::wostream out(&conv_out);
      std::cout << "Sending UCS4 data to std::cout via wbuffer_convert:\n";
      out << L"z\u00df\u6c34\U0001f34c\n";
  }

Output:


  Reading from a UTF-8 stringbuf via wbuffer_convert produces
  0x7a
  0xdf
  0x6c34
  0x1f34c
  Sending UCS4 data to std::cout via wbuffer_convert:
  zß水🍌