UML24 — isDerived with DefaultValue

I think derived properties should not have default values, since they are calculated from other info in the model and not from those default values.

Here is a list of such derived properties in the metamodel:

PropertyIsDerivedWithDefaultValue : 13
property = <Property> UML::State::/ isSubmachineState : Boolean
defaultValue = <Literal Boolean> false
property = <Property> UML::State::/ isSimple : Boolean
defaultValue = <Literal Boolean> true
property = <Property> UML::State::/ isOrthogonal : Boolean
defaultValue = <Literal Boolean> false
property = <Property> UML::State::/ isComposite : Boolean
defaultValue = <Literal Boolean> false
property = <Property> UML::Operation::/ upper : UnlimitedNatural [0..1]
defaultValue = <Literal UnlimitedNatural> 1
property = <Property> UML::Operation::/ lower : Integer [0..1]
defaultValue = <Literal Integer> 1
property = <Property> UML::Operation::/ isUnique : Boolean
defaultValue = <Literal Boolean> true
property = <Property> UML::Operation::/ isOrdered : Boolean
defaultValue = <Literal Boolean> false
property = <Property> UML::MultiplicityElement::/ upper : UnlimitedNatural [0..1]
defaultValue = <Literal UnlimitedNatural > 1
property = <Property> UML::MultiplicityElement::/ lower : Integer [0..1]
defaultValue = <Literal Integer> 1
property = <Property> UML::Message::/ messageKind : MessageKind
defaultValue = <Instance Value> unknown
property = <Property> UML::ExtensionEnd::/ lower : Integer [0..1]
defaultValue = <Literal Integer > 0
property = <Property> UML::Extension::/ isRequired : Boolean
defaultValue = <Literal Boolean> false

do we need to fix them?

The FTF agrees that these default values are meaningless, and in many cases confusing. Remove them