This commit is contained in:
terik23 2019-04-14 19:35:07 +05:00
parent b68625ca7a
commit e48ca6469d

View file

@ -119,30 +119,13 @@ template <typename E, E V>
}
template <typename E, int O, int... I>
[[nodiscard]] constexpr decltype(auto) enum_strings_impl(std::integer_sequence<int, I...>) noexcept {
[[nodiscard]] constexpr decltype(auto) enum_names_impl(std::integer_sequence<int, I...>) noexcept {
static_assert(std::is_enum_v<E>, "nameof::detail::enum_strings_impl requires enum type.");
constexpr std::array<std::string_view, sizeof...(I)> names{{enum_name_impl<E, static_cast<E>(I + O)>()...}};
return names;
}
template <typename E, typename U = std::underlying_type_t<E>>
[[nodiscard]] constexpr std::string_view nameof_enum_impl(int value) noexcept {
static_assert(std::is_enum_v<E>, "nameof::detail::nameof_enum_impl requires enum type.");
static_assert(enum_range<E>::max > enum_range<E>::min, "nameof::enum_range requires max > min.");
constexpr int max = enum_range<E>::max < (std::numeric_limits<U>::max)() ? enum_range<E>::max : (std::numeric_limits<U>::max)();
constexpr int min = enum_range<E>::min > (std::numeric_limits<U>::min)() ? enum_range<E>::min : (std::numeric_limits<U>::min)();
constexpr auto range = std::make_integer_sequence<int, max - min + 1>{};
constexpr auto names = enum_strings_impl<E, min>(range);
const int i = value - min;
if (i >= 0 && static_cast<std::size_t>(i) < names.size()) {
return names[i];
} else {
return {}; // Value out of range.
}
}
template <typename T>
struct check final {
using type = void;
@ -153,6 +136,7 @@ using check_t = typename check<T>::type;
template <typename T>
[[nodiscard]] constexpr std::string_view nameof_impl(std::string_view name, bool with_template_suffix) noexcept {
static_assert(std::is_void_v<T>, "nameof::detail::nameof_impl requires void type.");
if (name.length() >= 1 && (name.front() == '"' || name.front() == '\'')) {
return {}; // Narrow multibyte string literal.
} else if (name.length() >= 2 && name[0] == 'R' && (name[1] == '"' || name[1] == '\'')) {
@ -231,17 +215,28 @@ template <typename T>
template <typename T>
[[nodiscard]] constexpr std::string_view nameof_raw_impl(std::string_view name) noexcept {
static_assert(std::is_void_v<T>, "nameof::detail::nameof_raw_impl requires void type.");
return name;
}
} // namespace nameof::detail
// Obtains simple (unqualified) string enum name of enum variable.
template <typename E, typename D = std::decay_t<E>, typename = std::enable_if_t<std::is_enum_v<D>>>
template <typename E, typename D = std::decay_t<E>, typename U = std::underlying_type_t<D>, typename = std::enable_if_t<std::is_enum_v<D>>>
[[nodiscard]] constexpr std::string_view nameof_enum(E value) noexcept {
static_assert(std::is_enum_v<D>, "nameof::nameof_enum requires enum type.");
static_assert(enum_range<D>::max > enum_range<D>::min, "nameof::enum_range requires max > min.");
constexpr int max = enum_range<D>::max < (std::numeric_limits<U>::max)() ? enum_range<D>::max : (std::numeric_limits<U>::max)();
constexpr int min = enum_range<D>::min > (std::numeric_limits<U>::min)() ? enum_range<D>::min : (std::numeric_limits<U>::min)();
constexpr auto range = std::make_integer_sequence<int, max - min + 1>{};
constexpr auto names = detail::enum_names_impl<D, min>(range);
const int i = static_cast<int>(value) - min;
return detail::nameof_enum_impl<D>(static_cast<int>(value));
if (i >= 0 && static_cast<std::size_t>(i) < names.size()) {
return names[i];
} else {
return {}; // Value out of range.
}
}
// Obtains string name of type.