R503 - modelint/shlaer-mellor-metamodel GitHub Wiki

R503 / 1:M

State Model specifies period of time as one or many Non Deletion State

Non Deletion State partitions time period on exactly one State Model

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Regardless of purpose, Lifecycle or Assigner, every State Model requires at least one Non Deletion State to provide any utility. This distinction is made because an Assigner may not include any Deletion State.

But since the whole purpose of a State Model is to partition a time period into multiple contexts, multiple States are essential, but not strictly required. There is no harm in creating a State Model with a single State.

A Non Deletion State is, by definition, part of a single State Model.