#---
# 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 subclass scoping and method chaining


class PrimaryConfigurationRules < ConfigurationBuilder
  def run
    item(:secure_air_vent)

    item(:acid_bath).
      uses(acid.
         type(:hcl).
         grade(5)).
      uses(electricity(12))

    item(:camera).uses(electricity(1))

    item(:small_power_plant).
      provides(electricity(11)).
      depends_on(:secure_air_vent)
  end
end