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R110 / 1:Mc

Class is standpoint of zero one or many Perspective

Perspective is taken from exactly one Class

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A perspective is the point of view of an arbitrary instance to the instance to which it is mapped on some Association. This point of view is named with a phrase like mails package to and specifies a multiplicity and conditionality.

If the Association is reflexive, an instance may be mapped to itself, for example: Company A mails package to Company A. In this case the same instance holds two Perspectives on a single reflexive Association.

A Unary Association will have only one Perspective labeled that is perceived from the standpoint of either mapped instance. For example, Venezuela is adjacent to Brazil is exactly the same fact as Brazil is adjacent to Venezuela. The perspective is adjacent to:many:unconditional in this case is symmetric and reflexive and, thus, Unary.

A Class that does not participate in any Association will not be the source or destination of any Perspective.

Formalization

Perspective.(Viewed class, Domain) -> Class.(Name, Domain)