class Aquarium::InvarCond

   # File examples/design_by_contract_example.rb
60 def initialize 
61   @invar = 0
62 end

   # File examples/design_by_contract_example.rb
67 def bad_action
68   p "inside :bad_action"
69   @invar = 1
70 end

   # File examples/design_by_contract_example.rb
64 def good_action
65   p "inside :good_action"
66 end