The design and application of structured types in Ptolemy II

✍ Scribed by Yang Zhao; Yuhong Xiong; Edward A. Lee; Xiaojun Liu; Lizhi C. Zhong

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 616 KB
• Volume: 25
• Category: Article
• ISSN: 0884-8173
• DOI: 10.1002/int.20391

✦ Synopsis

Ptolemy II is a component-based design and modeling environment. It has a polymorphic type system that supports both base types and structured types, such as arrays, records, and unions. This paper presents the extensions to the base type system that support structured types. In the base type system, all the types are organized into a type lattice, and type constraints in the form of inequalities can be solved efÞciently over the lattice. We take a hierarchical and granular approach to add structured types to the lattice and extend the format of inequality constraints to allow arbitrary nesting of structured types. We also analyze the convergence of the constraint-solving algorithm on an inÞnite lattice after structured types are added. To show the application of structured types, we present two Ptolemy II models that have direct real-world background. The Þrst one describes the workßow of a charity organization, and the second one implements part of the IEEE 802.11 speciÞcation. These models make extensive use of record and union types to represent structured information.