Hi, I’m an utter newbie to Ruby (and OOP!) and I thought I’d share my
very first project. It’s nothing special - just a simple class that
simulates a deck of cards, but I’d like to get your comments to see if
there’s anything I can do better (enjoy!):
class Deck
@@Cards =
[‘Two’,‘Three’,‘Four’,‘Five’,‘Six’,‘Seven’,‘Eight’,‘Nine’,‘Ten’,‘Jack’,‘Queen’,‘King’,‘Ace’]
@@Suits = [‘Spades’,‘Hearts’,‘Diamonds’,‘Clubs’]
def initialize @top_card = -1 @deck = []
52.times do |card| @deck << card
end
end
def draw @top_card = @top_card + 1
if @top_card < 52 @deck[@top_card]
else
raise ‘There are only 52 cards in a deck!’
end
end
def shuffle @top_card = -1 @deck = @deck.sort_by {rand}
end
def suit
@@Suits[@top_card/13]
end
def face
factor = @top_card/13
index = @top_card - 13*factor
@@Cards[index]
end
As a newcomer, you are in a perfect position to learn how to properly
document your work. Not only “proper” in your eyes, but it is so easy
to make it compatible with rdoc. For instance:
Has properties resembling that of a deck of cards
Class Deck
##
# Constructs and returns an instance of Deck
#
def initialize
.......
end
##
# Does some action to an instance of Deck. Argument foo must be
of type string…
#
def bar(foo=nil)
…
end
end
Running this through rdoc will quickly create some helpful results,
especially as your code grows and you begin to reuse as much as
possible.
On Tue, 2007-04-24 at 06:16 +0900, Peter M. wrote:
def initialize @deck[@top_card]
def suit
@top_card=card
end
end
–
Thanks,
Ken M.
Wireless Operations Engineer
Farmers Wireless
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Hi, I’m an utter newbie to Ruby (and OOP!) and I thought I’d share my
very first project. It’s nothing special - just a simple class that
simulates a deck of cards, but I’d like to get your comments to see if
there’s anything I can do better (enjoy!):
This is indeed not a bad attempt at all, however
class Deck
@@Cards =
[‘Two’,‘Three’,‘Four’,‘Five’,‘Six’,‘Seven’,‘Eight’,‘Nine’,‘Ten’,‘Jack’,‘Queen’,‘King’,‘Ace’]
@@Suits = [‘Spades’,‘Hearts’,‘Diamonds’,‘Club’]
Personally I dislike class variables (I prefer class instance
variables even if the make the code more clumpsy (clumpsier?)) but
here it seems to me that constants would be in order, the name of the
cards and suits are constant in the domain after all.
Cards = %w{ Deuce Three Four Five …
Suits = %w{ Spades Hearts Diamonds Clubs }
def initialize @top_card = -1 @deck = []
52.times do |card| @deck << card
end
I will play my personal Ace of Trumps here @deck = [*0…51]
end
def draw @top_card = @top_card + 1 @top_card += 1
if @top_card < 52 @deck[@top_card]
else
raise ‘There are only 52 cards in a deck!’
end @deck[@top_card] or raise “There are only 42 cards in the deck ;)”
def face
factor = @top_card/13
index = @top_card - 13*factor
@@Cards[index]
replace the three by
Cards[ @top_card % 13 ]
end
The above two methods seem wrong to me, is it not @deck[@top_card]
that you want?
def set_card(card)
@top_card=card
end
No idea what that should do? If it were not for this method I would
get rid of @top_card at all in your code and write it as follows
def initialize; shuffle end
def shuffle; @deck = [*0…51].sort_by{ rand } end
def draw; @deck.shift or raise “Error only 42 cards” end
def face; Cards[@deck.first % 13] end
def suit; Suits[@deck.first / 13] end
Hi, I’m an utter newbie to Ruby (and OOP!) and I thought I’d share my
very first project. It’s nothing special - just a simple class that
simulates a deck of cards, but I’d like to get your comments to see if
there’s anything I can do better (enjoy!):
This is indeed not a bad attempt at all, however
…
HTH
Robert
There are a lot of things in your post that’re really great and have
helped develop my (still limited) knowledge of Ruby.
I don’t quite understand this, however:
Cards = %w{ Deuce Three Four Five …
Suits = %w{ Spades Hearts Diamonds Clubs }
From what I’ve been able to work out it converts everything between {}
into a string and then sticks that all in an array that Cards or Suits
points to. Is this correct?
Also
@deck[@top_card] or raise “There are only 42 cards in the deck ;)”
I understand what this means, but I’m unsure how to integrate this into
my code.
Thanks for your help!
P.S. I implimented the whole ‘@top_card’ system so that deck[] would not
have to be refilled with numbers each time it was shuffled - I had
worries about speed but perhaps in this case they were a bit to extreme.
Hi, I’m an utter newbie to Ruby (and OOP!) and I thought I’d share my
very first project. It’s nothing special - just a simple class that
simulates a deck of cards, but I’d like to get your comments to see if
there’s anything I can do better (enjoy!):
Others have commented your code, so I’ll just share a Deck class I
made for some little things. It may give you some ideas or maybe
someone else will comment on it. It can contain any object, not just
normal cards. Also I want to implement some shuffle methods that
resembled a human shuffle (with it’s fuzziness) apart from the actual
random sorting, but never got to do it, I just implemented a fuzzy cut
in half. Here it is:
require ‘emptydeckerror’
class Deck
def initialize
@deck = []
end
def << (item)
@deck << item
self
end
def draw
item = @deck.shift
raise EmptyDeckError, "The deck is empty" if !item
item
Cards = %w{ Deuce Three Four Five …
Suits = %w{ Spades Hearts Diamonds Clubs }
From what I’ve been able to work out it converts everything between {}
into a string and then sticks that all in an array that Cards or Suits
points to. Is this correct?
Cards = %w{ Deuce Three Four Five …
Suits = %w{ Spades Hearts Diamonds Clubs }
From what I’ve been able to work out it converts everything between {}
into a string and then sticks that all in an array that Cards or Suits
points to. Is this correct?
# Constructs and returns an instance of Deck
........
end
end
Running this through rdoc will quickly create some helpful results,
especially as your code grows and you begin to reuse as much as
possible.
Peter - Agile thinking has some interesting ideas about comments that
you should read up on as well before you dive in and comment every
little thing in your code. Essentially, comments are an additional
maintenance burden (you have to change them when you change your
code), and they become a liability if they stray from reality (which
they often do). While there are definitely times when comments are
useful, there are also times when they add very little or no value, in
which case you should prefer well named classes and methods that tell
their own story.
You can find a plethora of varying opinions about this if you google
“code smell comments”.
