Higher Order Connectors

A critical issue for architectural design is the nature of the glue, or connectors, with which a system's parts are combined. Thus an important rst step toward improving our ability to compose parts is to make to make connectors explicit semantic enties, where they can be documented, analyzed, and (sometimes) used to generate code. A number of notations for software architecture do precisely this. However, a key second step is to understand operations over connectors. In principle, such operations would permit one to produce new connectors out of old ones, adapt existing connectors to new contexts of use, and factor out common properties of connectors so they can be reused. In this paper we argue that the use of \higher order connectors" is one way to achieve this goal.