From: Trans <transfire@...>
Date: 2007-03-14T22:47:09+09:00
Subject: Nil Comparable

Does anyone see anything problematic about this?

  class NilClass

    include Comparable

    def <=>(x)
      x.nil? ? 0 : -1
    end

    def succ; nil; end

  end

It seems benign enough, and can be used to represent "always before".
For instance, in Rake there is a class called EarlyTime: "EarlyTime is
a fake timestamp that occurs before any other time value." And that's
all that it does. If NilClass were comparable per the above then
EarlyTime would not be needed.

T.