KERML — Behavior portions must be classified by the same behavior they are portions of

[Filed for Mr. Raphael Barbau] Clause 9.2.4.1 (Occurrences Overview), under Portions, first paragraph, the last sentence says

They must be classified the same way as the Occurrences they are portionsOf, or more specialized.

For a behavior with mandatory steps (features with lower multiplicity>1 typed by behaviors), this means every portion of its performances, including every snapshot, would need to have values for these steps, even when the steps are not intended to happen during/inside of that portion. Likewise for a structure with mandatory parts, eg, like an engine in a car, all spaceslices would need to have this part. The semantic above is not math/modeled.

Revise portion semantic constraints

This resolution addresses the stated issue by removing the statement that portions "must be classified the same way as the Occurrences they are portionsOf, or more specialized." (9.2.4.1 Occurrences Overview), which is not currently formally enforced by any constraint. It also adds a semantic constraint requiring a portion Feature owned by a Class to specialize Occurrence::portions. The proposed OCL is exactly parallel to the existing semantic constraint checkFeatureSuboccurrenceSpecialization that reauires a composite Feature to specialize Occurrence::suboccurrences.