SIL Transformations on Sequence Edges

Abstract

Introduction In this note a number of transformations on SIL graphs is described. Most emphasis will be on the transformations in which sequence edges play a crucial role. For a better understanding of the transformations and in order to be able to prove the correctness of the transformations, some attention will be given to the formal semantical model of SIL which is currently being developed. Notice however that the formal semantical model of SIL is still in its pre-development stage and only part of the available information is used. The informal semantics of SIL are explained in #Klo-91#. This note is set up in the following way. First we will explain the formal semantical model with emphasis on modelling behaviour and order, as far this is necessary for proving the transformations. The semantical components which constitute a SIL-graph are de#ned together with the composition rules. Thereafter the division of a SIL-graph in transformation blocks is explained. These trans