An Integrated Metamodel for OCL Types


	 Authors: Thomas Baar and Reiner Hähnle


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  The main objectives of OCL are to restrict UML models by additional
  constraints and to clarify the definition of the UML meta model.
  For certain applications, however, it is crucial for the
    modeler to have a flexible and precisely defined access mechanism
  to the meta level of UML models.  In the present paper we sketch
  such a modeling scenario and we argue that the current definition of
  OclType is insufficient. We propose an alternative definition
  based on metamodeling the type system of OCL in such a way that it
  is fully integrated with the UML meta model. This also clarifies
  some ambiguous issues in the OCL language specification and makes
  the reflexion mechanisms in OCL explicit.