NAME¶

std::wbuffer_convert::wbuffer_convert - std::wbuffer_convert::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 <codecvt>
#include <iostream>
#include <locale>
#include <sstream>

int main()
{
// Wrap a UTF-8 string stream in a UCS4 wbuffer_convert
std::stringbuf utf8buf("z\u00df\u6c34\U0001f34c");
// or "\x7a\xc3\x9f\xe6\xb0\xb4\xf0\x9f\x8d\x8c"
// or u8"zß水🍌"
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: "
<< std::hex << std::showbase;
for (wchar_t c; ucsbuf.get(c);)
std::cout << static_cast<std::wint_t>(c) << ' ';

// 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 << "\nSending UCS4 data to std::cout via wbuffer_convert: ";
out << L"z\u00df\u6c34\U0001f34c\n";
}

Output:¶

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