Refactor: Eliminate two each in Ruby [closed]

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I am trying to generate all poker cards (52 of cards), here is how I do it:

ranks = '23456789TJQKA'.split ''
suits = 'SHDC'.split ''
my_deck = []

ranks.each do |r|
  suits.each { |s| my_deck << r+s }
end

my_deck # => ["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"]

My friends who use python shows me this:

[r+s for r in '23456789TJQKA' for s in 'SHDC']

Does anyone could give me advice on how to make the above code more beautiful as the Python version? Thank you in advance.

Answer 1

Another way to write this using Array#product:

ranks = %w(2 3 4 5 6 7 8 9 T J Q K A)
suits = %w(S H D C)

my_deck = ranks.product(suits).map(&:join)
#=> ["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"]

Answer 2

It’s a matter of opinion. You could use %w() instead of the .split, more descriptive variable names, string interpolation, and the more idiomatic map rather than the iterative programming-esque eachs.

ranks = %w{2 3 4 5 6 7 8 9 T J Q K A}
suits = %w{S H D C}

my_deck = ranks.map{|rank| suits.map{|suit| "#{rank}#{suit}" }}.flatten