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Perspective is a Symmetric Perspective or Asymmetric Perspective

Every Perspective specifies a name, multiplicity, and conditionality and is specified relative to some Class. Taking an autonomous driving application, for example, a Perspective might be: is attempting to enter:one:conditional:Driving Lane.

An Asymmetric Perspective can be on either side of a Binary Association while a Symmetric Perspective is fixed to its only available side. This specialization makes it possible to capture this paired/single arrangement for the two kinds of Association.

<subclass>.(Rnum, Domain) -> Perspective.(Rnum, Domain)

In the case of a T or P Perspective subclass, the value of Side must be either T or P. For a Symmetric Perspective, the value of Side must be S.