22 General utilities library [utilities]

22.11 Class type_­index [type.index]

22.11.2 type_­index overview [type.index.overview]

namespace std { class type_index { public: type_index(const type_info& rhs) noexcept; bool operator==(const type_index& rhs) const noexcept; bool operator< (const type_index& rhs) const noexcept; bool operator> (const type_index& rhs) const noexcept; bool operator<=(const type_index& rhs) const noexcept; bool operator>=(const type_index& rhs) const noexcept; strong_ordering operator<=>(const type_index& rhs) const noexcept; size_t hash_code() const noexcept; const char* name() const noexcept; private: const type_info* target; // exposition only // Note that the use of a pointer here, rather than a reference, // means that the default copy/move constructor and assignment // operators will be provided and work as expected. }; }
The class type_­index provides a simple wrapper for type_­info which can be used as an index type in associative containers and in unordered associative containers.