18 Language support library [language.support]

18.7 Type identification [support.rtti]

18.7.4 Class bad_typeid [bad.typeid]

namespace std {
  class bad_typeid : public exception {
  public:
    bad_typeid() noexcept;
    bad_typeid(const bad_typeid&) noexcept;
    bad_typeid& operator=(const bad_typeid&) noexcept;
    const char* what() const noexcept override;
  };
}
1

The class bad_typeid defines the type of objects thrown as exceptions by the implementation to report a null pointer in a typeid expression ([expr.typeid]).

bad_typeid() noexcept;

2

Effects: Constructs an object of class bad_typeid.

bad_typeid(const bad_typeid&) noexcept; bad_typeid& operator=(const bad_typeid&) noexcept;

3

Effects: Copies an object of class bad_typeid.

const char* what() const noexcept override;

4

Returns: An implementation-defined ntbs.

5

Remarks: The message may be a null-terminated multibyte string ([multibyte.strings]), suitable for conversion and display as a wstring ([string.classes], [locale.codecvt])