deep_each.rb - a multidimensional each for Ruby

deep_each.rb

two_d_grid =
  [
    [ 1,   2,   3,   4,  5 ],
    [ 6,   7,   8,   9,  10 ],
    [ 11,  12,  13,  14, 15]
  ]

puts "Basic 2D each"
two_d_grid.each do |row|
  row.each do |cell|
    puts "Cell: #{cell}"
  end
end

three_d_grid =
  [
    [
      [ 1,  2,  3],
      [ 4,  5,  6]
    ],
    [
      [ 7,  8,  9],
      [10, 11, 12]
    ],
    [
      [13, 14, 15],
      [16, 17, 18]
    ]
  ]

puts "Basic 3D each"
three_d_grid.each do |plane|
  plane.each do |row|
    row.each do |cell|
      puts "Cell: #{cell}"
    end
  end
end

uneven_dimensional_grid =
  [
    1,
    [2, 3, 4],
    [
      [5, 6, 7],
      [8, 9, 10]
    ],
    11,
    [
      [
        [12],
        13
      ],
      14
    ],
    15
  ]

def deep_each(object, &block)
  traverser = lambda do |obj|
    if obj.respond_to?(:each)
      obj.each(&traverser)
    else
      block.call obj
    end
  end

  traverser.call object
end

puts "2D deep each"
deep_each(two_d_grid) do |cell|
  puts "Cell: #{cell}"
end

puts "3D deep each"
deep_each(three_d_grid) do |cell|
  puts "Cell: #{cell}"
end

puts "Uneven D deep each"
deep_each(uneven_dimensional_grid) do |cell|
  puts "Cell: #{cell}"
end

module Enumerable
  def deep_each(&block)
    traverser = lambda do |obj|
      if obj.respond_to?(:each)
        obj.each(&traverser)
      else
        block.call obj
      end
    end

    traverser.call self
  end
end

puts "Monkeypatched Enumerable deep each"
uneven_dimensional_grid.deep_each do |cell|
  puts "Cell: #{cell}"
end