virtual protected member function
        bool do_is (mask m, charT c) const;
const charT* do_is (const charT* low, const charT* high, mask* vec) const;

Classify characters [virtual]

Virtual protected member function in charge of classifying characters as described in public member function is (see ctype::is for details).

Polymorphic derived classes can redefine the behavior of this function.

See also