operator overloading

[jaded7]

suppose you have this snippet:

    ifstream fin("test.txt");
    if(fin) // this operator
    {
        // stuff
    }

How do I overload the operator here? I know that you can overload the logical negation operator:

bool operator!() const;

But I want to know how to define the operator shown above, but have no idea what the prototype is.

[vlad from moscow]

#include <iostream>

int main()
{
   struct A
   {
      explicit operator bool() const { return ( true ); }
   };

   if ( A() ) std::cout << "It works indeed!" << std::endl;

   return 0;
}

[jaded7]

perfect, thank you.

[MiiNiPaa]

What are you trying to do?
Do you want this:

    ifstream fin("test.txt");
    if(fin.is_open()) // this operator
    {
        // stuff
    }