From: Daniel Schierbeck <daniel.schierbeck@...>
Date: 2006-07-08T20:42:17+09:00
Subject: Re: newbie Q - calling a method for an object in an .each bl

Robert Klemme wrote:
> You could for example create individual classes for suit, face and
> maybe also for value implementing the enum pattern, so you end up
> having just a single instance for hearts, clubs, face_up, face_down
> etc.

I'd much rather stick with a single class, and use some of Ruby's 
goodness to get the magic:

   class Card
     SUITS = [:hearts, :clubs, :diamonds, :spades]
     RANKS = (1..13).to_a

     attr_reader :suit, :rank

     def initialize(suit, rank)
       @suit, @rank = suit.to_sym, rank.to_int

       raise unless SUITS.include? @suit
       raise unless RANKS.include? @rank
     end

     # creates the methods #hearts?, #clubs?, #diamonds?, and #spades?
     SUITS.each{|suit| define_method("#{suit}?"){ suit == @suit }}

     # etc. etc.
   end


But that's a matter of opinion, of course.


Cheers,
Daniel