TDL: a language for transition diagrams in the derivation of LOTOS specifications

Introduces a formalism which allows LOTOS specifications to be given in the form of transition diagrams (TDs). We argue that being able to use TDs as a design notation for LOTOS specifications would increase the quality of the software produced via a formal method, and ultimately this enhances LOTOS's acceptance by industry. The basis of our argument is that TDs are well-known and can be readily supported by tools. Thus, TDs are a user-friendly and effective tool for the design of LOTOS specifications. In order to support the design process, we define a simple language, called TDL (Transition Diagram Language), for expressing and manipulating TDs and as an intermediate language between TDs and LOTOS specifications. We provide a group of rules for translating TDs in TDL to basic LOTOS. We also enrich the basic LOTOS with some meta-combinators to facilitate the translation from TDs to LOTOS.