C++ << operator overloading

[Colossusx10]

I am trying to overload the << operator, and use it to print out a list.
For some reason, it isn't working out.

Here's my class deifnition:

class JGAirlines
{

	friend ostream &operator<<(ostream &,JGAirlines &);    
      
	public:
		JGAirlines(int,int);  // Constructor
		~JGAirlines(); // Destructor
		void RegisterPassenger(); // Enters a passenger name.
		void RegisterPassenger(string);
		void Delete(); //Deletes a passenger from the flight roster.
		void PrintFlightManifest();
		bool FindPassenger(string); //Finds a passenger on a flight.
		void Together(); //Registers passengers flying together.
		void Merge(); //Merges two flights.
		void Seat(); //Assigns seat numbers to all passengers.
		void ReadFile(); //Reads a set of passengers from a file.
		
		

	private:
            
        struct AirNode // node that represents passenger record
        {
			string person; // passenger's name
			AirNode *next; // pointer to the next passenger record
        };
		
		int flightID; // unique ID of the flight
		int maxSize; // maximum capacity of the flight
		int size; // number of passengers on board
		AirNode *head; // head of the linked list of passengers in alphabetical order
		
};



#endif

		
};



#endif

The function:

ostream &operator<<(ostream &output, JGAirlines &getPassenger)
{
	for(JGAirlines *current = getPassenger.head; current != NULL; current = current->next)
	{
		output << current->person <<endl; 
	}

	return output; 
}

When I compile I get these messages:
error C2440: 'initializing' : cannot convert from 'JGAirlines::AirNode *' to 'JGAirlines *'

error C2039: 'next' : is not a member of 'JGAirlines'

error C2039: 'person' : is not a member of 'JGAirlines'

I tried using:

friend ostream &operator<<(ostream &,AirNode&);

Instead of:

friend ostream &operator<<(ostream &,JGAirlines &);

but it still doesn't work.
Can anyone tell me what I'm doing wrong?

 

[bassman]

The errors have nothing to do with the operator overload. Just as the error messages suggest, I suggest you look at the types in each part of the code that's causing an error.

Here is the code causing each error:

error C2440: 'initializing' : cannot convert from 'JGAirlines::AirNode *' to 'JGAirlines *' is caused by:

JGAirlines *current = getPassenger.head

error C2039: 'next' : is not a member of 'JGAirlines' is caused by:

current = current->next

error C2039: 'person' : is not a member of 'JGAirlines' is caused by:

current->person

 

[mikeblas]

What bassman said is right on. I think you might've confused yourself by embedding your struct within the scope of your class. Nothing wrong with that, and this is a good time to use such a technique ... but you need to understand the scoping rules and operators if you want to do it right.

 

[Colossusx10]

The errors have nothing to do with the operator overload. Just as the error messages suggest, I suggest you look at the types in each part of the code that's causing an error.

Here is the code causing each error:

error C2440: 'initializing' : cannot convert from 'JGAirlines::AirNode *' to 'JGAirlines *' is caused by:

JGAirlines *current = getPassenger.head

error C2039: 'next' : is not a member of 'JGAirlines' is caused by:

current = current->next

error C2039: 'person' : is not a member of 'JGAirlines' is caused by:

current->person

Yes, I understand what the errors mean. I guess I should have stated the question clearer. What I meant to ask was, can anyone tell me how to fix it?

 

[AdamBomb]

Like Colossusx10 said, look at the types. What types are current and getPassenger.head, and why can't you assign one to the other?

 

[bassman]

Yes, I understand what the errors mean. I guess I should have stated the question clearer. What I meant to ask was, can anyone tell me how to fix it?

I don't think anyone is going to tell you *how* to fix it - but we will give you hints so you learn what the problem is on your own. AdamBomb gave a great hint about the first error.

For the second and third errors, look at exactly which class/struct directly contains next and person. Does the class pointed to by current contain them?