gistfile1.rb

require 'date'
require 'time'
require 'active_support/all'

p_inf = 1.0 / 0.0
n_inf = -1.0 / 0.0

module InfiniteComparable
  extend ActiveSupport::Concern

  included do
    class_exec do
      alias_method :old_comp, :<=>
      remove_method :<=>
    end
  end

  def <=> (other)
    conversion = :"to_#{self.class.name.downcase}"
    if other.respond_to?(:infinite?) && other.infinite?
      -other.infinite?
    elsif other.respond_to?(conversion)
      old_comp other.send(conversion)
    else
      old_comp other
    end
  end
end

module FloatInfiniteComparable
  extend ActiveSupport::Concern

  included do
    class_exec do
      alias_method :old_comp, :<=>
      remove_method :<=>
    end
  end

  def <=>(other)
    return old_comp(other) if other.class == self.class

    return 0 if other.respond_to?(:infinite?) && infinite? && infinite? == other.infinite?

    infinite? || old_comp(other)
  end
end

class Date
  include InfiniteComparable
end

class DateTime
  include InfiniteComparable
end

class Time
  include InfiniteComparable
end

class BigDecimal
  include FloatInfiniteComparable
end


class Float
  include FloatInfiniteComparable
end

p 1.0 <=> 10.0

p Float::INFINITY <=> Float::INFINITY
p -Float::INFINITY <=> -Float::INFINITY
p -Float::INFINITY <=> Float::INFINITY
p Float::INFINITY <=> -Float::INFINITY
p (1.0...10.0).include?((1.0...10.0))

time_zone = ActiveSupport::TimeZone['Eastern Time (US & Canada)']

time = Time.now
date = Date.today
datetime = DateTime.now
twz = ActiveSupport::TimeWithZone.new(time, time_zone)


p(Date.today <=> (Time.now + 10.years))
p(Time.now <=> (Date.today - 10.years))

p((Time.now + 10.years) <=> Date.today)
p((Date.today - 10.years) <=> Time.now)

p((DateTime.now + 10.years) <=> Date.today)
p((Date.today - 10.years) <=> DateTime.now)

p((twz + 10.years) <=> Date.today)
p((Date.today - 10.years) <=> twz)

p Range.new(Date.today, p_inf).include?(Time.now + 10.years)
p Range.new(n_inf, Date.today).include?(Time.now - 10.years)
p Range.new(Time.now, p_inf).include?(Date.today + 10.years)
p Range.new(n_inf, Time.now).include?((Date.today - 10.years))

p Range.new(Date.today, p_inf).include?(DateTime.now + 10.years)
p Range.new(n_inf, Date.today).include?(DateTime.now - 10.years)
p Range.new(Time.now, p_inf).include?(DateTime.now + 10.years)
p Range.new(n_inf, Time.now).include?((DateTime.now - 10.years))

p Range.new(Date.today, p_inf).include?(twz + 10.years)
p Range.new(n_inf, Date.today).include?(twz - 10.years)
p Range.new(Time.now, p_inf).include?(twz + 10.years)
p Range.new(n_inf, Time.now).include?((twz - 10.years))

p Range.new(Date.today, p_inf).include?(twz - 10.years)
p Range.new(n_inf, Date.today).include?(twz + 10.years)
p Range.new(Time.now, p_inf).include?(twz - 10.years)
p Range.new(n_inf, Time.now).include?((twz + 10.years))