clipboard_observer.rb

#!/usr/bin/env ruby
# For OS X

require 'optparse'

class NilClass
  def present?
    false
  end
end


class String
  def present?
    length > 0
  end
end


def observe(delay)
  before_pb = `pbpaste`
  loop do
    sleep(delay)
    puts before_pb \
      if before_pb != `pbpaste` && (before_pb = `pbpaste`).present?
  end
end


if $0 == __FILE__
  params = ARGV.getopts('d:', 'delay:')
  delay = (params['delay'] || params['d'] || 0.2).to_f
  observe(delay)
end