bool do_is(mask m, charT c) const;
const charT* do_is(const charT* low, const charT* high, mask* vec) const;
const charT* do_scan_is(mask m, const charT* low, const charT* high) const;
const charT* do_scan_not(mask m, const charT* low, const charT* high) const;
charT do_toupper(charT c) const;
const charT* do_toupper(charT* low, const charT* high) const;
charT do_tolower(charT c) const;
const charT* do_tolower(charT* low, const charT* high) const;
charT do_widen(char c) const;
const char* do_widen(const char* low, const char* high, charT* dest) const;
char do_narrow(charT c, char dfault) const;
const charT* do_narrow(const charT* low, const charT* high, char dfault, char* dest) const;