From: ahoward <ahoward@...>
Date: 2003-03-22T05:04:59+09:00
Subject: Re: infinite Time (solved)

On Sat, 22 Mar 2003 nobu.nokada@softhome.net wrote:

> You need to coerce.

thanks!  didn't know Time.coerce existed...

> Float#> doesn't call <=> due to performance.

but

  class << INF
    include Comparable
    ...
  end

should create a '>' correct?


anyhow, this seems to work fine :

----CUT----
  class Time
    INF   = INFINITY          =  1.0 / 0
    NINF  = NEGATIVE_INFINITY = -1.0 / 0
    EPOCH = Time.at(0)

    class << INFINITY
      include Comparable
      def <=> o;id == o.id ? 0 : 1;end
    end

    class << NEGATIVE_INFINITY
      include Comparable
      def <=> o;self.id == o.id ? 0 : -1;end
    end

    def coerce(x)
      case x
      when Float
	return [x, to_f]
      when Integer
	return [x, to_i]
      else
	super
      end
    end
  end

# a test
  def display command
    puts "\t#{command}"
    puts "\t\t# >> #{eval command}"
  end

  $now = Time.now
  objects = %w(Time::INF Time::NINF $now)

  objects.map do |a|
    puts '========'
    objects.map do |b|
      puts "\t--------"
      %w(<=> <= >= < > ==).map do |op|
	display "#{a} #{op} #{b}"
      end
    end
  end
----CUT----

-a

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