# File lib/dm-core/associations/many_to_many.rb, line 10
      def self.setup(name, model, options = {})
        assert_kind_of 'name',    name,    Symbol
        assert_kind_of 'model',   model,   Model
        assert_kind_of 'options', options, Hash

        repository_name = model.repository.name

        model.class_eval "def \#{name}(query = {})\n\#{name}_association.all(query)\nend\n\ndef \#{name}=(children)\n\#{name}_association.replace(children)\nend\n\nprivate\n\ndef \#{name}_association\n@\#{name}_association ||= begin\nunless relationship = model.relationships(\#{repository_name.inspect})[\#{name.inspect}]\nraise ArgumentError, \"Relationship \#{name.inspect} does not exist in \\\#{model}\"\nend\nassociation = Proxy.new(relationship, self)\nparent_associations << association\nassociation\nend\nend\n", __FILE__, __LINE__

        opts = options.dup
        opts.delete(:through)
        opts[:child_model]              ||= opts.delete(:class_name)  || Extlib::Inflection.classify(name)
        opts[:parent_model]             =   model
        opts[:repository_name]          =   repository_name
        opts[:remote_relationship_name] ||= opts.delete(:remote_name) || Extlib::Inflection.tableize(opts[:child_model])
        opts[:parent_key]               =   opts[:parent_key]
        opts[:child_key]                =   opts[:child_key]
        opts[:mutable]                  =   true

        names        = [ opts[:child_model], opts[:parent_model].name ].sort
        model_name   = names.join.gsub("::", "")
        storage_name = Extlib::Inflection.tableize(Extlib::Inflection.pluralize(names[0]) + names[1])

        opts[:near_relationship_name] = Extlib::Inflection.tableize(model_name).to_sym

        model.has(model.n, opts[:near_relationship_name])

        relationship = model.relationships(repository_name)[name] = RelationshipChain.new(opts)

        unless Object.const_defined?(model_name)
          model = DataMapper::Model.new(storage_name)

          model.class_eval "def self.name; \#{model_name.inspect} end\ndef self.default_repository_name; \#{repository_name.inspect} end\ndef self.many_to_many; true end\n", __FILE__, __LINE__

          names.each do |n|
            model.belongs_to(Extlib::Inflection.underscore(n).gsub("/", "_").to_sym, :class_name => n)
          end

          Object.const_set(model_name, model)
        end

        relationship
      end