quirky_songs.rb

# The MIT License
# 
# All contents Copyright (c) 2004-2008 Reginald Braithwaite
# <http://braythwayt.com>  except as otherwise noted.
# 
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
# 
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
# 
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.
# 
# http://www.opensource.org/licenses/mit-license.php

require 'quirky_bird'
require 'blank_slate'
require 'returning'

quirky_bird_extend(:maybe) do |value|
  if value.nil?
    returning(BlankSlate.new) do |it|
      def it.method_missing(*args)
        nil
      end
    end
  else
    value
  end
end

quirky_bird_extend(:try) do |value|
  returning(BlankSlate.new) do |it|
    def it.__value__=(arg)
       @value = arg
    end
    def it.method_missing(name, *args)
      if @value.respond_to?(name)
        @value.send(name, *args)
      end
    end
    it.__value__ = value
  end
end