Comparable Range - union, intersect, and check for overlap/less than/greater than with 2 ranges

comparable_range.rb

class ComparableRange < Range
  include Comparable

  def self.new(r_start, r_end = nil, exclusive = false)
    r_end ||= r_start
    r_start, r_end = r_end, r_start if r_end < r_start
    super
  end

  def overlaps(other)
    return cover? other unless other.is_a? Range
    cover? other.min or cover? other.max or other.cover? min or other.cover? max
  end

  def include?(other)
    if other.is_a? Range
      cover? other.min and cover? other.max
    else
      super
    end
  end

  def compare(other)
    if other.is_a? Range
      return 0 if overlaps(other)
      return -1 if max < other.min
      +1
    else
      return 0 if cover? other
      return -1 if max < other
      +1
    end
  end

  alias_method :<=>, :compare

  def intersection(other)
    fail ArgumentError.new('Other should be a range') unless other.is_a? Range
    return nil unless overlaps(other)
    new_min = [min, other.min].max
    new_max = [max, other.max].min
    self.class.new(new_min, new_max)
  end

  alias_method :|, :intersection

  def union(other)
    fail ArgumentError.new('Other should be a range') unless other.is_a? Range
    new_min = [min, other.min].min
    new_max = [max, other.max].max
    self.class.new(new_min, new_max)
  end

  alias_method :&, :union

end