what does this function declaration mean in c++

Question

virtual const char* what() const throw()
{

}

AFAIK it\'s a function that will return a constant pointer to a mutable char. The rest I am not sure.

Answer 1

1. virtual this one is used to overridden in derived class from base class
2. const char* This is a pointer to a constant character
3. what Returns a null-terminated character sequence that may be used to identify any exception
4. throw() parameter inside the throw is empty so it will call std::unexpected for all exception

#include
#include

class Myexception:public exception
{
    virtual const char* what() const throw()
    {
        return "My exception here";
    }
} myex;

int main()
{
    try() 
    {
        throw myex;
    }
    catch(exception &e)
    {
        cout<