Extend Ruby Enumerable with `#each_cycling_slice`, which cycles though the given list of slice sizes/widths.

cycling_slicer.rb

class CyclingSlicer

  def initialize(slices)
    @slices  = slices.cycle
    @slice   = @slices.next
    @counter = 0
  end

  def slice?
    @counter += 1

    return false unless @counter % @slice == 0

    @slice   = @slices.next
    @counter = 0

    true
  end

end

module Enumerable

  # Slice with a cycling list of slice widths.
  #
  # @example
  #   (1..12).each_cycling_slice(1, 2, 3) do |slice|
  #     p slice
  #   end
  #   # => [1]
  #   # => [2, 3]
  #   # => [4, 5, 6]
  #   # => [7]
  #   # => [8, 9]
  #   # => [10, 11, 12]

  def each_cycling_slice(*slices, &block)
    slices = [1] if slices.empty?
    slicer = CyclingSlicer.new(slices)

    slice_after { slicer.slice? }.each(&block)
  end

end