|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Defined in header <any> | ||
class bad_any_cast:publicstd::bad_cast | (since C++17) | |
Defines a type of object to be thrown by the value-returning forms ofstd::any_cast on failure.
Contents |
(constructor) | constructs a newbad_any_cast object(public member function) |
operator= | replaces thebad_any_cast object(public member function) |
what | returns the explanatory string (public member function) |
bad_any_cast()noexcept; | (1) | (since C++17) |
bad_any_cast(const bad_any_cast& other)noexcept; | (2) | (since C++17) |
Constructs a newbad_any_cast object with an implementation-defined null-terminated byte string which is accessible throughwhat().
std::bad_any_cast thenstd::strcmp(what(), other.what())==0.| other | - | another exception object to copy |
bad_any_cast& operator=(const bad_any_cast& other)noexcept; | (since C++17) | |
Assigns the contents with those ofother. If*this andother both have dynamic typestd::bad_any_cast thenstd::strcmp(what(), other.what())==0 after assignment.
| other | - | another exception object to assign with |
*this
virtualconstchar* what()constnoexcept; | (since C++17) | |
Returns the explanatory string.
Pointer to an implementation-defined null-terminated string with explanatory information. The string is suitable for conversion and display as astd::wstring. The pointer is guaranteed to be valid at least until the exception object from which it is obtained is destroyed, or until a non-const member function (e.g. copy assignment operator) on the exception object is called.
Implementations are allowed but not required to overridewhat().
[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] |
#include <any>#include <cassert>#include <print> int main(){auto x=std::any(42);assert(std::any_cast<int>(x)==42);// OK try{[[maybe_unused]]auto s=std::any_cast<std::string>(x);// throws}catch(const std::bad_any_cast& ex){std::println("{}", ex.what());}}
Possible output:
bad any_cast
