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

Defined in header <locale> 
std::size_t converted() const noexcept;

Returns the number of source characters that were processed by the most recent from_bytes() or to_bytes().

Return value

The number of characters consumed by the most recent conversion operation.

Example

#include <iostream>
#include <string>
#include <locale>
#include <codecvt>
int main()
{
    std::string utf8 =  u8"z\u00df\u6c34\U0001d10b"; // or u8"zß水𝄋"
                        // or "\x7a\xc3\x9f\xe6\xb0\xb4\xf0\x9d\x84\x8b";
    std::cout << "original UTF-8 string size: " << utf8.size() << '\n';
 
    // the UTF-8 - UTF-32 standard conversion facet
    std::wstring_convert<std::codecvt_utf8<char32_t>, char32_t> cvt;
 
    // UTF-8 to UTF-32
    std::u32string utf32 = cvt.from_bytes(utf8);
    std::cout << "UTF-32 string size: " << utf32.size() << '\n';
    std::cout << "converted() == " << cvt.converted() << '\n';
    // UTF-32 to UTF-8
    utf8 = cvt.to_bytes(utf32);
    std::cout << "new UTF-8 string size: " << utf8.size() << '\n';
    std::cout << "converted() == " << cvt.converted() << '\n';
}

Output:

original UTF-8 string size: 10
UTF-32 string size: 4
converted() == 10
new UTF-8 string size: 10
converted() == 4

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 2174 C++11 wstring_convert::converted was not required to be noexcept required

See also

converts a wide string into a byte string
(public member function)
converts a byte string into a wide string
(public member function)

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