R997

R997 / 1:1c

Migrate Action migrates instances in exactly one Instance Flow

Instance Flow provides instances for migration to zero or one Migrate Action

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One or more instances to be migrated is supplied to the Migrate Action. These instances and possibly some related Facets may be deleted in the process of migration.

There are many possible consumers of an Instance Flow with a Migrate Action being just one of them. But if a Migrate Action is supplied, there can only be one since once an instance Migrates it will be deleted.

A Migrate Action requires a set of instances to be migrated. If the set is empty there is no error as the empty set is not treated as a special case.

Formalization

Migrate Action.(Instances to migrate, Activity, Domain) -> Instance Flow.(Flow, Activity, Domain)