Experiments with a High-Level Navigation Language

Writing navigation expressions is an important part of the task of developing a model transformation de nition. When navigation is complex and the size of source models is signi cant, performance issues cannot be neglected. Model transformation languages often implement some variants of OCL as their navigation language. Writing e cient code in OCL is usually a di cult task because of the nature of the language and the lack of optimizing OCL compilers. Moreover, optimizations generally reduce readability. An approach to tackle this issue is to raise the level of abstraction of the navigation language. We propose to complement the regular navigation language of model transformation languages with a high-level navigation language, in order to improve both performance and readability. This paper reports on the initial results of our experiments creating the HLN language: a declarative high-level navigation language. We will motivate the problem, and will we describe the language as well as the main design guidelines.