#---
# Excerpted from "The ThoughtWorks Anthology",
# published by The Pragmatic Bookshelf.
# Copyrights apply to this code. It may not be used to create training material, 
# courses, books, articles, and the like. Contact us if you are in doubt.
# We make no guarantees that this code is fit for any purpose. 
# Visit http://www.pragmaticprogrammer.com/titles/twa for more book information.
#---
# Using explicit receivers


ConfigurationBuilder.start do |config|
  config.item :secure_air_vent

  config.item(:acid_bath) do |item|
    item.uses(Resources.acid) do |acid|
      acid.type = :hcl
      acid.grade = 5
    end
    item.uses(Resources.electricity(12))
  end

  config.item(:camera) do |item|
    item.uses(Resources.electricity(1))
  end

  config.item(:small_power_plant) do |item|
    item.provides(Resources.electricity(11))
    item.depends_on(:secure_air_vent)
  end
end