How to write a compacted card deck generator? - ruby

Question

I am writing a card deck generator, here is the solution I come up with, but I found it spans multiple lines and doesn't look good, is there any other way to build this card?
deck = []
'23456789TJQKA'.each_char do |rank|
'SHDC'.each_char do |suit|
deck << rank + suit
end
end

Answer 1

You can use Array#product to produce Cartesian product from two arrays.
# ruby 2.0
deck = '23456789TJQKA'.chars.product('SHDC'.chars).map{|a| a.join}
# ruby 1.9
deck = '23456789TJQKA'.split(//).product('SHDC'.split(//)).map{|a| a.join}
As DNNX commented, you can use .map(&:join) to get a shorter one.
However, I think it's better to write a clear program than a compact one.

Answer 2

As an example of using a block variant product(other_ary, ...) { |p| block }
deck = []
'23456789TJQKA'.split('').product('SHDC'.split('')){|el| deck << el.join}

Answer 3

As Arie suggested, it's better to write a clear program than a shorter one. I think this one is dead simple:
deck = %w(2S 2H 2D 2C
3S 3H 3D 3C
4S 4H 4D 4C
5S 5H 5D 5C
6S 6H 6D 6C
7S 7H 7D 7C
8S 8H 8D 8C
9S 9H 9D 9C
TS TH TD TC
JS JH JD JC
QS QH QD QC
KS KH KD KC
AS AH AD AC)
Just kidding.