Standard library header <typeindex> (C++11)

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This header is part of the type support library.

Includes

(C++20)
Three-way comparison operator support

Classes

wrapper around a type_info object, that can be used as index in associative and unordered associative containers
(class)
hash support for std::type_index
(class template specialization)
Forward declarations
Defined in header <functional>
(C++11)
hash function object
(class template)

Synopsis

#include <compare>
 
namespace std {
  class type_index;
  template<class T> struct hash;
  template<> struct hash<type_index>;
}

Class std::type_index

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.
  };
}