# File lib/core/facets/range/within.rb, line 49
  def umbrella(r)
    s = first <=> r.first
    e = r.last <=> last

    if e == 0
      if r.exclude_end? and exclude_end?
        e = r.max <=> max
      else
        e = (r.exclude_end? ? 0 : 1) <=> (exclude_end? ? 0 : 1)
      end
    end

    return s,e
  end