module Comparable

def <(other)
  (self <=> other) == -1
end

def <=(other)
  (self <=> other) <= 0
end

def ==(other)
  (self <=> other) == 0
end

def >(other)
  (self <=> other) == 1
end

def >=(other)
  (self <=> other) >= 0
end

def between?(min, max)
  self > min && self < max
end