“…Systems such as PAISLey [ZS86], RSL/REVS [BBD77], SARA [EFRV86], Data Flow Diagram Designs [War86], Jackson System Development [Cam86], and USE [WPSK86], are examples of such previous environments. While certainly valuable for their intended purposes, each of these systems provides support for the creation of a relatively narrow range of software objects by relatively restrictive and inflexible processes.…”