std::isalnum(std::locale)
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Defined in header
<locale>
template< class CharT >
bool isalnum( CharT ch, const locale& loc );
bool isalnum( CharT ch, const locale& loc );
Checks if the given character is classified as an alphanumeric 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 alphanumeric, false otherwise.
[edit] Possible implementation
template<class CharT> bool isalnum(CharT ch, const std::locale & loc) { return std::use_facet <std::ctype <CharT>>(loc).is(std::ctype_base::alnum, ch); }
[edit] Example
Demonstrates the use of isalnum() with different locales (OS-specific).
Run this code
#include <iostream> #include <locale> int main() { const wchar_t c = L'\u2135'; // mathematical symbol aleph std::locale loc1("C"); std::cout << "isalnum('א', C locale) returned " << std::boolalpha << std::isalnum (c, loc1) << '\n'; std::locale loc2("en_US.UTF-8"); std::cout << "isalnum('א', Unicode locale) returned " << std::boolalpha << std::isalnum (c, loc2) << '\n'; }
Possible output:
isalnum('א', C locale) returned false
isalnum('א', Unicode locale) returned true