Abstract

Program comprehension is an essential part of software engineering. The paper describes the constructivist theory of comprehension, a process based on assimilation and accommodation of knowledge. Assimilation means that the new facts are either added to the existing knowledge or rejected. Accommodation means that the existing knowledge is reorganized in order to absorb new facts. These processes are illustrated by case studies of knowledge-level reengineering of a legacy program and of incremental change. In both cases, we constructed preliminary knowledge from the program documentation, and then adjusted it by comprehending the actual code. The case studies supported constructivism as a suitable theory of program comprehension.