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std::bad_exception

From cppreference.com
< cpp‎ | error
 
 
Utilities library
General utilities
Relational operators (deprecated in C++20)
 
 
 
Defined in header <exception>
class bad_exception;

std::bad_exception is the type of the exception thrown by the C++ runtime in the following situations:

  • If std::exception_ptr stores a copy of the caught exception and if the copy constructor of the exception object caught by std::current_exception throws an exception, the captured exception is an instance of std::bad_exception.
(since C++11)
  • If a dynamic exception specification is violated and std::unexpected throws or rethrows an exception that still violates the exception specification, but the exception specification allows std::bad_exception, std::bad_exception is thrown.
(until C++17)
cpp/error/exceptionstd-bad exception-inheritance.svg

Inheritance diagram

All member functions of std::bad_exception are constexpr.

(since C++26)

Contents

[edit] Member functions

constructs the bad_exception object
(public member function)
copies the object
(public member function)
[virtual]
returns the explanatory string
(virtual public member function)

Inherited from std::exception

Member functions

[virtual]
destroys the exception object
(virtual public member function of std::exception) [edit]
[virtual]
returns an explanatory string
(virtual public member function of std::exception) [edit]

[edit] Notes

Feature-test macro Value Std Feature
__cpp_lib_constexpr_exceptions 202411L (C++26) constexpr for exception types

[edit] Example

Compiles only in C++14 or earlier modes (may issue warnings).

#include <exception>
#include <iostream>
#include <stdexcept>
 
void my_unexp()
{
    throw;
}
 
void test()
    throw(std::bad_exception) // Dynamic exception specifications
                              // are deprecated in C++11
{
    throw std::runtime_error("test");
}
 
int main()
{
    std::set_unexpected(my_unexp); // Deprecated in C++11, removed in C++17
 
    try
    {
        test();
    }
    catch (const std::bad_exception& e)
    {
        std::cerr << "Caught " << e.what() << '\n';
    }
}

Possible output:

Caught std::bad_exception