std::ctype<CharT>::toupper, std::ctype<CharT>::do_toupper

Header: <locale>

1,2) Public member function, calls the protected virtual member function do_toupper of the most derived class.

# Declarations

public:
CharT toupper( CharT c ) const;

public:
const CharT* toupper( CharT* beg, const CharT* end ) const;

protected:
virtual CharT do_toupper( CharT c ) const;

protected:
virtual const CharT* do_toupper( CharT* beg, const CharT* end ) const;

# Parameters

c: character to convert
beg: pointer to the first character in an array of characters to convert
end: one past the end pointer for the array of characters to convert

# Notes

Only 1:1 character mapping can be performed by this function, e.g. the uppercase form of ‘ß’ is the two-character string “SS” (with some exceptions - see «Capital ẞ»), which cannot be obtained by do_toupper.

# Example

#include <iostream>
#include <locale>
 
void try_upper(const std::ctype<wchar_t>& f, wchar_t c)
{
    wchar_t up = f.toupper(c);
    if (up != c)
        std::wcout << "Upper case form of \'" << c << "' is " << up << '\n';
    else
        std::wcout << '\'' << c << "' has no upper case form\n";
}
 
int main()
{
    std::locale::global(std::locale("en_US.utf8"));
    std::wcout.imbue(std::locale());
    std::wcout << "In US English UTF-8 locale:\n";
    auto& f = std::use_facet<std::ctype<wchar_t>>(std::locale());
    try_upper(f, L's');
    try_upper(f, L'ſ');
    try_upper(f, L'δ');
    try_upper(f, L'ö');
    try_upper(f, L'ß');
 
    std::wstring str = L"Hello, World!";
    std::wcout << "Uppercase form of the string '" << str << "' is ";
    f.toupper(&str[0], &str[0] + str.size());
    std::wcout << '\'' << str << "'\n";
}