Standard library header <exception>

 

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Standard library headers

Language support <cfloat> <climits> <compare> (C++20) <contracts> (C++26) <coroutine> (C++20) <csetjmp> <csignal> <cstdarg> <cstddef> <cstdint> (C++11) <cstdlib> <exception> <initializer_list> (C++11)    <limits> <new> <source_location> (C++20) <stdfloat> (C++23) <typeinfo> <version> (C++20) Concepts <concepts> (C++20) Diagnostics <cassert> <cerrno> <debugging> (C++26) <stacktrace> (C++23) <stdexcept> <system_error> (C++11) Memory management <memory> <memory_resource> (C++17) <scoped_allocator> (C++11) Metaprogramming <type_traits> (C++11) <ratio> (C++11)

General utilities <any> (C++17) <bitset> <bit> (C++20) <charconv> (C++17) <expected> (C++23) <format> (C++20) <functional> <optional> (C++17) <stdbit.h> (C++26) <tuple> (C++11) <typeindex> (C++11) <utility> <variant> (C++17) Containers <array> (C++11) <deque> <flat_map> (C++23) <flat_set> (C++23) <forward_list> (C++11) <hive> (C++26) <inplace_vector> (C++26)    <list> <map> <mdspan> (C++23) <queue> <set> <span> (C++20) <stack> <unordered_map> (C++11) <unordered_set> (C++11) <vector> Iterators <iterator> Ranges <generator> (C++23) <ranges> (C++20)

Algorithms <algorithm> <numeric> Strings <cctype> <cstring> <cuchar> (C++11) <cwchar> <cwctype> <string_view> (C++17) <string> Text processing <clocale> <codecvt> (C++11/17/26*) <locale> <regex> (C++11) <text_encoding> (C++26)    Numerics <cfenv> (C++11) <cmath> <complex> <linalg> (C++26) <numbers> (C++20) <random> (C++11) <simd> (C++26) <stdckdint.h> (C++26) <valarray> Time <chrono> (C++11) <ctime> C compatibility <ccomplex> (C++11/17/20*) <ciso646> (until C++20) <cstdalign> (C++11/17/20*) <cstdbool> (C++11/17/20*) <ctgmath> (C++11/17/20*)

Input/output <cinttypes> (C++11) <cstdio> <filesystem> (C++17) <fstream> <iomanip> <iosfwd> <iostream> <ios> <istream> <ostream> <print> (C++23) <spanstream> (C++23) <sstream> <streambuf> <strstream> (C++98/26*) <syncstream> (C++20) Concurrency support <atomic> (C++11) <barrier> (C++20) <condition_variable> (C++11) <future> (C++11) <hazard_pointer> (C++26) <latch> (C++20) <mutex> (C++11) <rcu> (C++26) <semaphore> (C++20) <shared_mutex> (C++14) <stdatomic.h> (C++23) <stop_token> (C++20) <thread> (C++11) Execution support <execution> (C++17)

 

This header is part of the error handling library.

Types
exception	base class for exceptions thrown by the standard library components (class)
nested_exception (C++11)	a mixin type to capture and store current exceptions (class)
bad_exception	exception thrown when std::current_exception fails to copy the exception object (class)
unexpected_handler (deprecated in C++11)(removed in C++17)	the type of the function called by std::unexpected (typedef)
terminate_handler	the type of the function called by std::terminate (typedef)
exception_ptr (C++11)	shared pointer type for handling exception objects (typedef)
Functions
unexpected (deprecated in C++11)(removed in C++17)	function called when dynamic exception specification is violated (function)
uncaught_exceptionuncaught_exceptions (removed in C++20*)(C++17)	checks if exception handling is currently in progress (function)
make_exception_ptr (C++11)	creates an std::exception_ptr from an exception object (function template)
current_exception (C++11)	captures the current exception in a std::exception_ptr (function)
rethrow_exception (C++11)	throws the exception from an std::exception_ptr (function)
throw_with_nested (C++11)	throws its argument with std::nested_exception mixed in (function template)
rethrow_if_nested (C++11)	throws the exception from a std::nested_exception (function template)
terminate	function called when exception handling fails (function)
get_terminate (C++11)	obtains the current terminate_handler (function)
set_terminate	changes the function to be called by std::terminate (function)
get_unexpected (deprecated in C++11)(removed in C++17)	obtains the current unexpected_handler (function)
set_unexpected (deprecated in C++11)(removed in C++17)	changes the function to be called by std::unexpected (function)

Synopsis

namespace std {
  class exception;
  class bad_exception;
  class nested_exception;

  using terminate_handler = void (*)();
  terminate_handler get_terminate() noexcept;
  terminate_handler set_terminate(terminate_handler f) noexcept;
  [[noreturn]] void terminate() noexcept;

  int uncaught_exceptions() noexcept;

  using exception_ptr = /* unspecified */;

  exception_ptr current_exception() noexcept;
  [[noreturn]] void rethrow_exception(exception_ptr p);
  template<class E> exception_ptr make_exception_ptr(E e) noexcept;

  template<class T> [[noreturn]] void throw_with_nested(T&& t);
  template<class E> void rethrow_if_nested(const E& e);
}

Class std::exception

namespace std {
  class exception {
  public:
    exception() noexcept;
    exception(const exception&) noexcept;
    exception& operator=(const exception&) noexcept;
    virtual ~exception();
    virtual const char* what() const noexcept;
  };
}

Class std::bad_exception

namespace std {
  class bad_exception : public exception {
  public:
    // see [exception] for the specification of the special member functions
    const char* what() const noexcept override;
  };
}

Class std::nested_exception

namespace std {
  class nested_exception {
  public:
    nested_exception() noexcept;
    nested_exception(const nested_exception&) noexcept = default;
    nested_exception& operator=(const nested_exception&) noexcept = default;
    virtual ~nested_exception() = default;

    // access functions
    [[noreturn]] void rethrow_nested() const;
    exception_ptr nested_ptr() const noexcept;
  };

  template<class T> [[noreturn]] void throw_with_nested(T&& t);
  template<class E> void rethrow_if_nested(const E& e);
}

See also

• Error handling