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std::isupper(std::locale)

Defined in header <locale>
template< class CharT >
bool isupper( CharT ch, const locale& loc );

Checks if the given character is classified as an uppercase alphabetic character by the given locale's std::ctype facet.

Parameters

ch - character
loc - locale

Return value

Returns true if the character is classified as uppercase, false otherwise.

Possible implementation

template< class CharT >
bool isupper( CharT ch, const std::locale& loc ) {
    return std::use_facet<std::ctype<CharT>>(loc).is(std::ctype_base::upper, ch);
}

Example

Demonstrates the use of std::isupper() with different locales (OS-specific).

#include <iostream>
#include <locale>
 
int main()
{
    const wchar_t c = L'\u00de'; // capital letter thorn
 
    std::locale loc1("C");
    std::cout << "isupper('Þ', C locale) returned "
               << std::boolalpha << std::isupper(c, loc1) << '\n';
 
    std::locale loc2("en_US.UTF8");
    std::cout << "isupper('Þ', Unicode locale) returned "
              << std::boolalpha << std::isupper(c, loc2) << '\n';
}

Possible output:

isupper('Þ', C locale) returned false
isupper('Þ', Unicode locale) returned true

See also

checks if a character is an uppercase character
(function)
checks if a wide character is an uppercase character
(function)

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