DS-Viewer. An interactive graphical data structure presentation facility

DS-Viewer is a tool that is the result of a research project in data structure presentation within a program state. This tool addresses two distinct issues in this area: (1) to effectively present data structures themselves for a given program state and (2) to present groups of data structures and their interrelationships as described by their pointer definitions. Graphical presentations were developed to address these issues. For the data structure presentation, the user is provided a display window for any single data structure instance formatted with its fields and field values. Flexibility in display is provided by allowing the user a choice from the various value formats for each field. For groups of data structure instances, a graphical drawing space is provided in which pictures of these data structure instances and their interrelationships are drawn as blocks and arrows. The computer assists the user in drawing such a picture by describing its components, allowing the user to choose which to draw and to construct as much of the picture as desired.