School of Computing

Reflections on the Object Constraint Language

A. Hamie, F. Civello, J. Howse, S. Kent, and M. Mitchell

In Post Workshop Proceedings of UML98, pages 182-196. Springer Verlag, June 1998.


The Object Constraint Language (OCL), which forms part of the UML set of modelling notations, is a precise, textual language for expressing constraints that cannot be shown diagrammatically in UML. This paper reflects on a number of aspects of the syntax and semantics of the OCL, and makes proposals for clarification or extension. Specifically, the paper suggests that: the concept of flattening collections of collections is unnecessary, state models should be connectable to class models, defining object creation should be made more convenient, OCL should be based on a 2-valued logic, set subtraction should be covered more fully, and a "let" feature should be introduced.

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Bibtex Record

author = {A. Hamie and F. Civello and J. Howse and S. Kent and M. Mitchell},
title = {{Reflections on the Object Constraint Language}},
month = {June},
year = {1998},
pages = {182-196},
keywords = {determinacy analysis, Craig interpolants},
note = {},
doi = {},
url = {},
    booktitle = {Post Workshop Proceedings of UML98},
    publisher = {Springer Verlag},

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