std::isalpha(std::locale)
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Defined in header
<locale>
template< class CharT >
bool isalpha( CharT ch, const locale& loc );
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.
[edit] Parameters
ch
-
character
loc
-
locale
[edit] Return value
Returns true if the character is classified as alphabetic, false otherwise.
[edit] 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); }
[edit] Example
Demonstrates the use of isalpha() with different locales (OS-specific).
Run this code
#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'; }
Possible output:
isalpha('Я', C locale) returned false
isalpha('Я', Unicode locale) returned true