std::bad_any_cast

Since C++17

Header: <any>

Defines a type of object to be thrown by the value-returning forms of std::any_cast on failure.

# Declarations

class bad_any_cast : public std::bad_cast;

(since C++17)

# Parameters

other: another exception object to copy

# Return value

*this

# Notes

Implementations are allowed but not required to override what().

# Example

#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());
    }
}