std::iswupper
Min standard notice:
Header: <cwctype>
Checks if the given wide character is an uppercase letter, i.e. one of ABCDEFGHIJKLMNOPQRSTUVWXYZ or any uppercase letter specific to the current locale.
# Declarations
int iswupper( std::wint_t ch );
# Parameters
ch: wide character
# Return value
Non-zero value if the wide character is an uppercase letter, zero otherwise.
# Notes
ISO 30112 specifies which Unicode characters are include in POSIX upper category.
# Example
#include <clocale>
#include <cwctype>
#include <iostream>
int main()
{
const wchar_t c = L'\u053d'; // Armenian capital letter xeh ('Խ')
std::cout << std::hex << std::showbase << std::boolalpha;
std::cout << "in the default locale, iswupper("
<< static_cast<std::wint_t>(c) << ") = "
<< static_cast<bool>(std::iswupper(c)) << '\n';
std::setlocale(LC_ALL, "en_US.utf8");
std::cout << "in Unicode locale, iswupper("
<< static_cast<std::wint_t>(c) << ") = "
<< static_cast<bool>(std::iswupper(c)) << '\n';
}