Using CLOS-like Concepts in a Prototyping System

Traditional languages like ADA use a model of sequential control with a side-effectable memory. Combination or aggregation mechanisms are used to compose complex data structures from simpler ones. Most programming languages provide extensive mechanisms for defining abstract data types from primitive ones, but very few programming languages provide mechanisms for defining control abstractions (besides procedures) or other non-data abstractions. We believe that prototyping is largely a process of composing or aggregating complex prototypes from simple ones, and sometimes such composition is performed with source code and sometimes not. Therefore, a prototyping environment is one whose primary function is to compose and control existing source and executable mixed language programs and modules.