XAda: an executable Ada design language methodology

A methodology for using Ada as an executable design language is presented. The methodology follows Booch's admonition to "Design a little--Code a little" [BOOCH1] to achieve a progressive demonstration of design correctness. Resource consuming, evolutionary, stubs are used to execute the software design as the design progresses, in order to demonstrate design self-consistency and proper loading on resources such as cpu operations and disk I/O. The methodology continues thru implementation if the programming language is Ada.