Example for Lipa

sun_system.rb

require 'lipa'

un = root :universe do
  kind :planet_system do
    num_planet run{
      count = 0
      children.values.each do |planet|
        count += 1 if planet.kind == :planet
      end
      count
    }
  end

  kind :planet do
    has_live false
    has_water false
    number 0
  end

  planet_system :sun_system do
    planet :mercury do
      number 1
      radius 46_001_210
    end

    planet :venus do
      number 2
      radius 107_476_259
    end

    planet :earth do
      number 3
      radius 147_098_074
      has_live true
      has_water true

      node :moon, :radius => 363_104
    end
  end
end


puts un.sun_system.earth.number
puts un.sun_system.earth.radius
puts un.sun_system.earth.has_live
puts un.sun_system.earth.has_water
puts un.sun_system.num_planet