Experience with a refinement paradigm in a knowledge-based automatic programming system
David R. Barstow · 1978
PECOS is a knowledge-based system that constructs concrete implementations of abstract algorithms in the domain of symbolic programming. The rules in PECOS's knowledge base deal explicitly with many details of symbolic programming, including intermediate-level constructs and certain design decisions. Programs are synthesized by gradually refining the original specification into a program in the target language. By applying the refinement rules in its knowledge base, PECOS constructs a refinement tree: the root is the abstract specification, each leaf is an alternative implementation, and each path is a different sequence of rule applications. Thus, PECOS can construct a variety of different implementations for the same abstract specification.