28 Localization library [localization]

28.4 Standard locale categories [locale.categories]

28.4.2 The ctype category [category.ctype]

28.4.2.4 ctype<char> specialization [facet.ctype.special]

28.4.2.4.5 Virtual functions [facet.ctype.char.virtuals]

char do_toupper(char) const; const char* do_toupper(char* low, const char* high) const; char do_tolower(char) const; const char* do_tolower(char* low, const char* high) const; virtual char do_widen(char c) const; virtual const char* do_widen(const char* low, const char* high, char* to) const; virtual char do_narrow(char c, char dfault) const; virtual const char* do_narrow(const char* low, const char* high, char dfault, char* to) const;
These functions are described identically as those members of the same name in the ctype class template ([locale.ctype.members]).