Structuring into subsystems: the experience of a prototyping approach

This paper describes our experience in the design of a complex system i n PASCAL . It only focuses on the specific moment in a top-down design whe n designers are trying to structure the system into subsystems . The applied methods are not specific to PASCAL and can be generalized t o other languages . These methods are based upon the idea that the structuring of a system into subsystems should be an iterative process . Unfortunately, this rarely occurs in practice, because interface s among subsystems generally need to be finalized at an early stage o f design when subsystems must be implemented by different programmers o r different teams of programmers . In our case, we adopted a prototyping attitude in the design phase which turned out to be valuable .