class Instance < ActiveRecord::Base

has_and_belongs_to_many :dependances,
  :class_name => 'Instance',
  :join_table => 'dependances_instances',
  :association_foreign_key => 'dependance_id'

has_and_belongs_to_many :instances,
  :class_name => 'Instance',
  :join_table => 'dependances_instances',
  :association_foreign_key => 'instance_id'

end