22 General utilities library [utilities]

22.14 Formatting [format]

22.14.4 Class template basic_format_string [format.fmt.string]

namespace std { template<class charT, class... Args> struct basic_format_string { private: basic_string_view<charT> str; // exposition only public: template<class T> consteval basic_format_string(const T& s); basic_format_string(runtime-format-string<charT> s) noexcept : str(s.str) {} constexpr basic_string_view<charT> get() const noexcept { return str; } }; }
template<class T> consteval basic_format_string(const T& s);
Constraints: const T& models convertible_to<basic_string_view<charT>>.
Effects: Direct-non-list-initializes str with s.
Remarks: A call to this function is not a core constant expression ([expr.const]) unless there exist args of types Args such that str is a format string for args.