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c++inheritanceoperator-overloadingiostreamfriend

c++ derived class accessing base class' friend operators

I am working with operator overloading and inheritance. I currently have something similar to the following code:

istream& operator >> (istream& in, derived& d)
{
   /* Some code asking for input to populate the object's data members*/
   cin >> d; /*Here, the operator called is this one, creating an infinite loop*/
}

The base class has an istream >> operator and when trying to invoke it, the operator actually calls itself, causing a loop. How can I access the base's operator from the derived's?

Solution

  • You need to convert it to the base class to call the operator>> on base class, otherwise it would try to call itself and lead to infinite recursion. E.g.

    istream& operator >> (istream& in, derived& d)
{
    in >> static_cast<base&>(d);
    return in;
}

    PS: You should use in instead of using cin fixedly, and return in in operator>>.