Describe the bug

In Gaphor, the Package.owningPackage and Package.packagedElement are both derived attributes. In the UML specification, they are not derived attributes. The setting of derived attribute values in Gaphor is supposed to occur as a side-effect of setting some other attribute value. I have been unable to identify the attribute whose value needs to be set in order to update owningPackage and packagedElement. I have tried setting the following attribute values, all of which produce an error.

event.memberNamespace = package
event.namespace = package
event.owner = package
event.owningPackage = package
event.package = package
package.member = event
package.ownedElement = event
package.ownedMember = event
package.ownedType = event
package.packagedElement = event

To Reproduce

Steps to reproduce the behavior:

1. Programmatically create a Package and an Event (or ChangeEvent)
2. Try setting any of the attributes above. An error message indicating that the attribute is a derived construct will occur.

Expected behavior

In the UML standard, neither Package.packagedElement nor PackagedElement.owningPackage are derived. They can be set directly. this is the expected behavior.

Screenshots

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OS

• Linux (Please put in notes the specific distro)
• macOS
• Windows

Version

Version of Gaphor: 2.26.0

Additional information

Add any other context about the problem here.