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14.3.16 nteractionOperand




    InteractionFragment (from BasicInteractions , Fragments ) on page 505


    Namespace (from Kernel ) on page 101


   Issue 7989 -Fix typo 8340 -fix typo

   An InteractionOperand is contained in a CombinedFragment . An InteractionOperand represents one operand of the expression given by the enclosing CombinedFragment .

   An InteractionOperand is an InteractionFragment with an optional guard expression. An InteractionOperand may be guarded by an InteractionConstraint . Only InteractionOperand s with a guard that evaluates to true at this point in the interaction will be considered for the production of the traces for the enclosing CombinedFragment .

   InteractionOperand contains an ordered set of InteractionFragments .

   Issue 8349 -replace ‘EventOccurrence’ by ‘OccurrenceSpecification’

   In Sequence Diagrams these InteractionFragments are ordered according to their geometrical position vertically. The geometrical position of the InteractionFragment is given by the topmost vertical coordinate of its contained OccurrenceSpecifications or symbols.



Issue 8349 - replace ‘EventOccurrence’ by ‘OccurrenceSpecification’

   [1] The guard must be placed directly prior to (above) the OccurrenceSpecification that will become the first OccurrenceSpecification within this InteractionOperand .

   [2] The guard must contain only references to values local to the Lifeline on which it resides, or values global to the whole Interaction (See InteractionConstraint (from Fragments ) on page 504).


   Only InteractionOperand s with true guards are included in the calculation of the semantics. If no guard is present, this is taken to mean a true guard.

   The semantics of an InteractionOperand is given by its constituent InteractionFragments combined by the implicit seq operation. The seq operator is described in CombinedFragment (from Fragments ) on page 487.


   InteractionOperand s are separated by a dashed horizontal line. The InteractionOperand s together make up the framed CombinedFragment .

   Within an InteractionOperand of a Sequence Diagram the order of the InteractionFragments are given simply by the topmost vertical position.

   See Figure 14.11 for examples of InteractionOperand .

Issue 8341 - replace ‘InteractionOperator’ with ‘InteractionOperatorKind