std::current_exception

Defined in header <exception>
std::exception_ptr current_exception()		(since C++11)

If called during exception handling (typically, in a catch clause), captures the current exception object and creates an std::exception_ptr that holds a reference to that exception object, or to a copy of that exception object (it is implementation-defined if a copy is made)

If the implementation of this function requires a call to new and the call fails, the returned pointer will hold a reference to an instance of std::bad_alloc

If the implementation of this function requires to copy the captured exception object and its copy constructor throws an exception, the returned pointer will hold a reference to the exception thrown. If the copy constructor of the thrown exception object also throws, the returned pointer may hold a reference to an instance of std::bad_exception to break the endless loop.

If the function is called when no exception is being handled, an empty std::exception_ptr is returned.

Parameters

(none)

Return value

An instance of std::exception_ptr holding a reference to the exception object, or a copy of the exception object, or to an instance of std::bad_alloc or to an instance of std::bad_exception.

Exceptions

noexcept specification:  

noexcept

  

Example

Run this code

#include <exception>
#include <iostream>
#include <stdexcept>
#include <string>
 
void handle_eptr(std::exception_ptr eptr) // passing by value is OK
{
    try
    {
        if (eptr)
            std::rethrow_exception(eptr);
    }
    catch(const std::exception& e)
    {
        std::cout << "Caught exception: '" << e.what() << "'\n";
    }
}
 
int main()
{
    std::exception_ptr eptr;
 
    try
    {
        [[maybe_unused]]
        char ch = std::string().at(1); // this generates a std::out_of_range
    }
    catch(...)
    {
        eptr = std::current_exception(); // capture
    }
 
    handle_eptr(eptr);
 
} // destructor for std::out_of_range called here, when the eptr is destructed

Possible output:

Caught exception: 'basic_string::at: __n (which is 1) >= this->size() (which is 0)'

See also

Template:cpp/error/dcl list exception ptrTemplate:cpp/error/dcl list rethrow exceptionTemplate:cpp/error/dcl list make exception ptr