Preface
Many modeling languages, such as the Unified Modeling Language (UML), advocate the
use of graphical notations for modeling. This kind of representations usually allow a nice
high level description of the system, while getting into details is more often left to textual
modeling or formal languages.
    The OCL’15 workshop, as previous editions, was aimed to serve as a forum were re-
searchers and practitioners could exchange ideas, experiences and results for the benefit
of both the software engineering community and the standards specifications. The work-
shop met its goal judging by the versatility of the contributions selected for discussion.
Indeed, the reader will find papers dealing with the applicability and limitations of con-
straints languages for adding precision to modeling and transformation languages, or to
bind modeling elements. Also, other works are concerned with the tool support for con-
straints and query languages, e.g., OCL lazy evaluation for large models, or version control
for textual modeling languages. Last but not least, semantics issues bring the question
of how specification standards should be enhanced, or how textual and visual notations
should be synchronized in order to assure consistency.
    Every accepted paper was reviewed by at least three members of the program com-
mittee. We wish to thank all authors and participants for their contributions to the
workshop, and reviewers for ensuring the proceedings quality. We would like to thank
the committees of Models 2015 for making this workshop possible, and organizing the
successful surrounding events in Ottawa.


October 2015                                                              Achim D. Brucker
                                                                              Marina Egea
                                                                            Martin Gogolla
                                                                            Frédéric Tuong




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