Hi Don: I would like to reactivate our collaboration so that users of Demeter/Java also benefit from your work. Our collaboration so far is archived in: http://www.ccs.neu.edu/research/demeter/design-decisions/collection-classes Do your generated collection classes implement the interface which Doug proposed? We generate accessor functions of the form get_x() for instance variable x. Will this be a problem? We were also talking about the reverse: combining Jakarta and Demeter. In Demeter/Java we have a nice traversal package which is very good at handling traversals of objects http://www.ccs.neu.edu/research/demeter/DemeterJava/use/ http://www.ccs.neu.edu/research/demeter/DemeterJava/use/latest-demjava/tg/ Traversals are probably common in Jakarta since it is a tool to build generators. To see the many traversals in Demeter/Java, see: http://www.ccs.neu.edu/research/demeter/DemeterJava/use/latest-demjava -- Karl