std::bad_exception

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std::bad_exception

Member functions
bad_exception::bad_exception
bad_exception::operator=
bad_exception::what

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Defined in header`<exception>`
class bad_exception:public exception

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

Ifstd::exception_ptr stores a copy of the caught exception and if the copy constructor of the exception object caught bystd::current_exception throws an exception, the captured exception is an instance of`std::bad_exception`.	(since C++11)
If adynamic exception specification is violated andstd::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)

Inheritance diagram

All member functions ofstd::bad_exception areconstexpr.

(since C++26)

[edit]Member functions

(constructor)	constructs the`bad_exception` object (public member function)
operator=	copies the object (public member function)
what [virtual]	returns the explanatory string (virtual public member function)

Inherited fromstd::exception

Member functions

(destructor) [virtual]	destroys the exception object (virtual public member function of`std::exception`)[edit]
what [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).

Run this code

#include <exception>#include <iostream>#include <stdexcept> void my_unexp(){throw;} void test()throw(std::bad_exception)// Dynamic exception specifications// are deprecated in C++11{throwstd::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';}}