ama-team / ruby-entity-mapper

    class Mapper

      class Type

        module BuiltIn

          # Pair class definition

          class HashTupleType < Type

            def initialize

              super(Aux::HashTuple, virtual: true)

              attribute!(:key, parameter!(:K))

              attribute!(:value, parameter!(:V))

              enumerator_block do |entity, type, *|

                ::Enumerator.new do |yielder|

                  yielder << [type.attributes[:key], entity.key, nil]

                  yielder << [type.attributes[:value], entity.value, nil]

                end

              end

            end

            INSTANCE = new

          end

        end

      end

    end