#---
# 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 hash based literals to encode everything


{:items => [
  {:id => :secure_air_vent},
  {:id => :acid_bath, 
    :uses => [
      [:acid, {:type => :hcl, :grade => 5}],
      [:electricity, 12]]},
  {:id => :camera,
    :uses => [:electricity, 1]},
  {:id => :small_power_plant,
    :provides => [:electricity, 11],
    :depends_on => :secure_air_vent}
  ]}