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- #ifndef ENTT_CORE_TYPE_INFO_HPP
- #define ENTT_CORE_TYPE_INFO_HPP
-
- #include <string_view>
- #include <type_traits>
- #include <utility>
- #include "../config/config.h"
- #include "../core/attribute.h"
- #include "fwd.hpp"
- #include "hashed_string.hpp"
-
- namespace entt {
-
- /**
- * @cond TURN_OFF_DOXYGEN
- * Internal details not to be documented.
- */
-
- namespace internal {
-
- struct ENTT_API type_index final {
- [[nodiscard]] static id_type next() ENTT_NOEXCEPT {
- static ENTT_MAYBE_ATOMIC(id_type) value{};
- return value++;
- }
- };
-
- template<typename Type>
- [[nodiscard]] constexpr auto stripped_type_name() ENTT_NOEXCEPT {
- #if defined ENTT_PRETTY_FUNCTION
- std::string_view pretty_function{ENTT_PRETTY_FUNCTION};
- auto first = pretty_function.find_first_not_of(' ', pretty_function.find_first_of(ENTT_PRETTY_FUNCTION_PREFIX) + 1);
- auto value = pretty_function.substr(first, pretty_function.find_last_of(ENTT_PRETTY_FUNCTION_SUFFIX) - first);
- return value;
- #else
- return std::string_view{""};
- #endif
- }
-
- template<typename Type, auto = stripped_type_name<Type>().find_first_of('.')>
- [[nodiscard]] static constexpr std::string_view type_name(int) ENTT_NOEXCEPT {
- constexpr auto value = stripped_type_name<Type>();
- return value;
- }
-
- template<typename Type>
- [[nodiscard]] static std::string_view type_name(char) ENTT_NOEXCEPT {
- static const auto value = stripped_type_name<Type>();
- return value;
- }
-
- template<typename Type, auto = stripped_type_name<Type>().find_first_of('.')>
- [[nodiscard]] static constexpr id_type type_hash(int) ENTT_NOEXCEPT {
- constexpr auto stripped = stripped_type_name<Type>();
- constexpr auto value = hashed_string::value(stripped.data(), stripped.size());
- return value;
- }
-
- template<typename Type>
- [[nodiscard]] static id_type type_hash(char) ENTT_NOEXCEPT {
- static const auto value = [](const auto stripped) {
- return hashed_string::value(stripped.data(), stripped.size());
- }(stripped_type_name<Type>());
- return value;
- }
-
- } // namespace internal
-
- /**
- * Internal details not to be documented.
- * @endcond
- */
-
- /**
- * @brief Type sequential identifier.
- * @tparam Type Type for which to generate a sequential identifier.
- */
- template<typename Type, typename = void>
- struct ENTT_API type_index final {
- /**
- * @brief Returns the sequential identifier of a given type.
- * @return The sequential identifier of a given type.
- */
- [[nodiscard]] static id_type value() ENTT_NOEXCEPT {
- static const id_type value = internal::type_index::next();
- return value;
- }
-
- /*! @copydoc value */
- [[nodiscard]] constexpr operator id_type() const ENTT_NOEXCEPT {
- return value();
- }
- };
-
- /**
- * @brief Type hash.
- * @tparam Type Type for which to generate a hash value.
- */
- template<typename Type, typename = void>
- struct type_hash final {
- /**
- * @brief Returns the numeric representation of a given type.
- * @return The numeric representation of the given type.
- */
- #if defined ENTT_PRETTY_FUNCTION
- [[nodiscard]] static constexpr id_type value() ENTT_NOEXCEPT {
- return internal::type_hash<Type>(0);
- #else
- [[nodiscard]] static constexpr id_type value() ENTT_NOEXCEPT {
- return type_index<Type>::value();
- #endif
- }
-
- /*! @copydoc value */
- [[nodiscard]] constexpr operator id_type() const ENTT_NOEXCEPT {
- return value();
- }
- };
-
- /**
- * @brief Type name.
- * @tparam Type Type for which to generate a name.
- */
- template<typename Type, typename = void>
- struct type_name final {
- /**
- * @brief Returns the name of a given type.
- * @return The name of the given type.
- */
- [[nodiscard]] static constexpr std::string_view value() ENTT_NOEXCEPT {
- return internal::type_name<Type>(0);
- }
-
- /*! @copydoc value */
- [[nodiscard]] constexpr operator std::string_view() const ENTT_NOEXCEPT {
- return value();
- }
- };
-
- /*! @brief Implementation specific information about a type. */
- struct type_info final {
- /**
- * @brief Constructs a type info object for a given type.
- * @tparam Type Type for which to construct a type info object.
- */
- template<typename Type>
- constexpr type_info(std::in_place_type_t<Type>) ENTT_NOEXCEPT
- : seq{type_index<std::remove_cv_t<std::remove_reference_t<Type>>>::value()},
- identifier{type_hash<std::remove_cv_t<std::remove_reference_t<Type>>>::value()},
- alias{type_name<std::remove_cv_t<std::remove_reference_t<Type>>>::value()} {}
-
- /**
- * @brief Type index.
- * @return Type index.
- */
- [[nodiscard]] constexpr id_type index() const ENTT_NOEXCEPT {
- return seq;
- }
-
- /**
- * @brief Type hash.
- * @return Type hash.
- */
- [[nodiscard]] constexpr id_type hash() const ENTT_NOEXCEPT {
- return identifier;
- }
-
- /**
- * @brief Type name.
- * @return Type name.
- */
- [[nodiscard]] constexpr std::string_view name() const ENTT_NOEXCEPT {
- return alias;
- }
-
- private:
- id_type seq;
- id_type identifier;
- std::string_view alias;
- };
-
- /**
- * @brief Compares the contents of two type info objects.
- * @param lhs A type info object.
- * @param rhs A type info object.
- * @return True if the two type info objects are identical, false otherwise.
- */
- [[nodiscard]] inline constexpr bool operator==(const type_info &lhs, const type_info &rhs) ENTT_NOEXCEPT {
- return lhs.hash() == rhs.hash();
- }
-
- /**
- * @brief Compares the contents of two type info objects.
- * @param lhs A type info object.
- * @param rhs A type info object.
- * @return True if the two type info objects differ, false otherwise.
- */
- [[nodiscard]] inline constexpr bool operator!=(const type_info &lhs, const type_info &rhs) ENTT_NOEXCEPT {
- return !(lhs == rhs);
- }
-
- /**
- * @brief Compares two type info objects.
- * @param lhs A valid type info object.
- * @param rhs A valid type info object.
- * @return True if the first element is less than the second, false otherwise.
- */
- [[nodiscard]] constexpr bool operator<(const type_info &lhs, const type_info &rhs) ENTT_NOEXCEPT {
- return lhs.index() < rhs.index();
- }
-
- /**
- * @brief Compares two type info objects.
- * @param lhs A valid type info object.
- * @param rhs A valid type info object.
- * @return True if the first element is less than or equal to the second, false
- * otherwise.
- */
- [[nodiscard]] constexpr bool operator<=(const type_info &lhs, const type_info &rhs) ENTT_NOEXCEPT {
- return !(rhs < lhs);
- }
-
- /**
- * @brief Compares two type info objects.
- * @param lhs A valid type info object.
- * @param rhs A valid type info object.
- * @return True if the first element is greater than the second, false
- * otherwise.
- */
- [[nodiscard]] constexpr bool operator>(const type_info &lhs, const type_info &rhs) ENTT_NOEXCEPT {
- return rhs < lhs;
- }
-
- /**
- * @brief Compares two type info objects.
- * @param lhs A valid type info object.
- * @param rhs A valid type info object.
- * @return True if the first element is greater than or equal to the second,
- * false otherwise.
- */
- [[nodiscard]] constexpr bool operator>=(const type_info &lhs, const type_info &rhs) ENTT_NOEXCEPT {
- return !(lhs < rhs);
- }
-
- /**
- * @brief Returns the type info object associated to a given type.
- *
- * The returned element refers to an object with static storage duration.<br/>
- * The type doesn't need to be a complete type. If the type is a reference, the
- * result refers to the referenced type. In all cases, top-level cv-qualifiers
- * are ignored.
- *
- * @tparam Type Type for which to generate a type info object.
- * @return A reference to a properly initialized type info object.
- */
- template<typename Type>
- [[nodiscard]] const type_info &type_id() ENTT_NOEXCEPT {
- if constexpr(std::is_same_v<Type, std::remove_cv_t<std::remove_reference_t<Type>>>) {
- static type_info instance{std::in_place_type<Type>};
- return instance;
- } else {
- return type_id<std::remove_cv_t<std::remove_reference_t<Type>>>();
- }
- }
-
- /*! @copydoc type_id */
- template<typename Type>
- [[nodiscard]] const type_info &type_id(Type &&) ENTT_NOEXCEPT {
- return type_id<std::remove_cv_t<std::remove_reference_t<Type>>>();
- }
-
- } // namespace entt
-
- #endif
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