Relationship - modelint/shlaer-mellor-metamodel GitHub Wiki

A Relationship describes time and instance invariant rules and policies that bind one or more Classes together in a Domain.

The concept of ‘time invariance’, means that the rules apply at all times. So a Departing Aircraft is directed to take-off from exactly one Runway, it is the case, at all times, that an instance of Departing Aircraft is related to exactly one Runway along the previously described Relationship.

By ‘instance invariant’ we mean that the rules abstracted by a Relationship apply universally to all instances of the participating Classes.

Identifiers

1. Rnum + Domain

Attributes

Rnum

A number of the form R<n> such as R1, R2, .... A numbering range is established for each Subsystem.

Type: Relationship Number, based on Nominal