Problem

(1..2).last != (1...3).last

Solution

class Range
  # http://bit.ly/p2rmyY
  # (1..2).last != (1...3).last
  # (1..2).last_element == (1...3).last_element
  def last_element
    exclude_end? ? last.pred : last
  end unless defined? last_element
end