Question

I’m trying to make a Blackjack simulation, below is the code…

one_suit = [2,3,4,5,6,7,8,9,10,10,10,10,11]; #the value of the cards for blackjack
full_deck = one_suit*4; #clubs, diamonds, hearts and spades
$deck = full_deck; #start off the game with a full deck

class Player
  attr_accessor :ace_count
  attr_accessor :hand_value

  def initialize(ace_count,hand_value)
    @ace_count  = ace_count;
    @hand_value = hand_value;
  end

  def self.hit
    choice_of_card = rand($deck.length); #choose a random card out of the deck
    drawn_card = $deck[choice_of_card]; #draw that random card from the deck
    if drawn_card != 0 #if there is a card there 
     $deck[choice_of_card] = 0; #remove that card from the deck by making the space blank
     if drawn_card == 11 #if you draw an ace
      self.ace_count += 1;
     end 
     self.hand_value += drawn_card ;
    else hit; #if there is no card at that space then redraw (recursion)
    end
  end

end

player1 = Player.new(0,0);
player1.hit;

However, when I run it I get the following output:

NoMethodError: undefined method `hit’ for # (root) at
C:\Users\Ernst\Documents\JRuby\blackjack.rb:30

What am I doing wrong? The method is defined within the class.

Answer 1

hit is a class method.

How can you call it with an object?

When you write self.method, it is defined as a class method.

To write an object or instance method just

use def method .. end

in your case

def hit
## remove `self` identifier from the attributes.
## e.g. ace_count += 1;
end

If you want to call class methods, you can use

Player.hit and not player_obj.hit

But i guess your need is to call object/instance methods, that you can do by removing self identifier.