Question

I am making a card game in ruby.

I have the Game class, which has an array of Player objects.

 array_of_players = Array[
  Player.new("Ben"),
  Player.new("Adam"),
  Player.new("Peter"),
  Player.new("Fred"),
 ]
 my_game = Game.new(array_of_players)

 puts my_game.players[2].name #=> Peter

Each player also has access to the Game, so that they can access the important bits of the game like so

self.game.last_card_dealt

Each player also has cards (Player.cards), and I want to make sure that players can’t access each other’s cards. However, the Game does need access to the cards, so I don’t think using private is appropriate, and the players need access to some of each other’s information, so I don’t think I want that to be private either…

Basically, I want these to work.

self.cards #where self is a Player object
self.players[0].cards #where self is the Game
self.game.players[0].name #where self is a Player object

And this to fail:

self.hand.players[0].cards  #=> Nice try sucker! Cheating is for losers.

How are more complex permissions like this handled?
Thanks.

Answer 1

Thanks for all your responses.

In the end I figured that I could give the authorised object a key which is used to allow it access to the meat of a method.

Game object has @auth_object and sets it to the player object it intends to access the secret methods of, and the player secret method checks if hand.auth_object is self, otherwise it does nothing. Then @auth_object is set back to nil. There is an attr_reader but no writer for @auth_object.

That works.