Control and definition modularization: an improved software design technique for organizing programs

The author proposes a technique called control and definition modularization (CDM), which derives a systematic program layout from a given structure chart using the concepts of `control' and `definition' modules. A control module includes processes for handling a conceptual data object not directly implementable. A definition module defines operations associated with a concrete data object implementable using a primitive or derived data type of a programming language. Grouping the operations available for each concrete data object, and keeping them separated from execution flow, improves programs maintainability. This technique extends the structured design methodology and provides designers with a systematic way of deriving informational strength modules as well as a structured physical layout from the structure chart. A program based on the CDM technique is easier to understand and maintain. This research makes a significant contribution toward bridging the gap between structured design and object-oriented concepts