How to reference functions from other classes to add value to vector

Question

I'm trying to add an Object to a vector using a setter function. My files are as follows

#ifndef ROOM_H
#define ROOM_H

#include <string>
#include <vector>
#include "User.h"
using namespace std;

class Room {
    vector<User> users;

public:
    Room();
    void addToRoom(User user);
    vector<User> getUsers();
};

#endif

addToRoom is just

users.push_back(user);

My user.h is

#ifndef USER_H
#define USER_H
#include <string>
#include <vector>

using namespace std;

class User {

        string password;
        string username;

public:
        User(string user, string pass);
        string getPass();
        string getName();
};

#endif

I am trying to do

void
IRCServer::addUser(int fd, const char * user, const char * password, const char * args)
{

        string myUsername = user;
        string myPassword = password;
        User *newUser = new User(myUsername, myPassword);
        Room *newRoom = new Room();
        newRoom->addToRoom(newUser);


        return;

}

However, if I pass in newUser, I get an error saying there is no matching function, there is no known conversion for argument 1 from 'User*' to 'User'. Passing &newUser says that there is no known conversion for argument 1 from 'User**' to 'User'. Do I need to alter my vectors, or is there another way to do this?

Answer 1

I suspect you are coming from Java. In C++, a typename indicates a value, not a reference, and you don't need to use new to allocate an object:

User newUser(myUsername, myPassword); // creates a User
Room newRoom;  // creates a Room
newRoom.addToRoom(newUser);

Answer 2

You are confusing a pointer to a User with the User itself. Your addToRoom function has a signature of void( )(User), but you're calling it with the signature void( )(User*).

In your particular example, there also isn't any reason to allocate memory with new. You can do everything by just creating objects on the stack.