< cpp‎ | locale
Defined in header <locale>
template< class charT >
bool isalpha( charT ch, const locale& loc );

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


ch - character
loc - locale

Return value

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

Possible implementation

template< class charT >
bool isalpha( charT ch, const std::locale& loc ) {
    return std::use_facet<std::ctype<charT>>(loc).is(std::ctype_base::alpha, ch);


Demonstrates the use of isalpha() with different locales (OS-specific).

#include <iostream>
#include <locale>
int main()
    const wchar_t c = L'\u042f'; // cyrillic capital letter ya
    std::locale loc1("C");
    std::cout << "isalpha('Я​', C locale) returned "
               << std::boolalpha << std::isalpha(c, loc1) << '\n';
    std::locale loc2("en_US.UTF8");
    std::cout << "isalpha('Я', Unicode locale) returned "
              << std::boolalpha << std::isalpha(c, loc2) << '\n';


isalpha('Я​', C locale) returned false
isalpha('Я', Unicode locale) returned true

See also

checks if a character is alphabetic
checks if a wide character is alphabetic