You are reading the documentation for Syside 0.11.0-rc.1, a pre-release. What it describes can still change before 0.11.0. The current release is 0.10.3. Go to the 0.10.3 documentation
flow-payload-feature
Available in: KerML, SysML
This checks that flows owns at most one payload feature.
This is impossible to trigger through textual syntax.
Specification
A Flow must have at most one owned_feature that is a PayloadFeature.
