Question

I ran into an issue google could not solve. Why is that cout works for an int object but not a string object in the following program?

#include<iostream>
using namespace std;
class MyClass {
    string val;
public:
    //Normal constructor.
    MyClass(string i) {
        val= i;
        cout << "Inside normal constructor\n";
    }
    //Copy constructor 
    MyClass(const MyClass &o) {
        val = o.val;
        cout << "Inside copy constructor.\n";
    }
    string getval() {return val; }
};
void display(MyClass ob)
{
    cout << ob.getval() << endl;    //works for int but not strings
}
int main()
{
    MyClass a("Hello");
    display(a);
    return 0;
}

Answer 1

You must include the string header to get the overloaded operator<<.

Also you might want to return a const string& instead of a string from getval, change your constructor to accept a const string& instead of a string, and change display to accept a const MyClass& ob to avoid needless copying.