ST6RI-935 KerML/SysML concrete-syntax conformance findings

[seidewitz]

This PR corrects non-conformities between the implementation and the KerML and SysML specification for the following textual notation grammar productions.

KerML

1. FeatureConjugation – A usage couldn't have a feature chain as he target of an owned conjugation.

   Specification

   OwnedConjugation : Conjugation =
         originalType = [QualifiedName]
       | originalType = FeatureChain
       { ownedRelatedElement += originalType }
   

   Old Implementation

   FeatureConjugation returns SysML::Conjugation :
       originalType = [SysML::Feature | QualifiedName ]
   ;
   

   Change. Added alternative ownedRelatedElement += OwnedFeatureChain.

2. MetadataFeatureDeclaration – Disallowed metadata features of the form @ : M. (@M with no colon parsed OK.)

   Specification

   MetadataFeatureDeclaration : MetadataFeature =
       ( Identification ( ':' | 'typed' 'by' ) )?
       ownedRelationship += OwnedFeatureTyping
   

   Old Implementation

   fragment MetadataFeatureDeclaration returns SysML::MetadataFeature :
       ( Identification ( ':' | 'typed' 'by' ) )? ownedRelationship += MetadataTyping
   ;
   

   Change. Changed Identification to Identification?. (Identification can be empty in the specification grammar but not in the implementation.)

SysML

4. GuardedSuccessionMember – Could not have a visibility keyword.

   Specification

   GuardedSuccessionMember : FeatureMembership =
       MemberPrefix ownedRelatedElement += GuardedSuccession
   

   Old Implementation

   GuardedSuccessionMember returns SysML::FeatureMembership :
       ownedRelatedElement += GuardedSuccession 
   ;
   

   Change. Added MemberPrefix.

5. InterfaceUsageDeclaration – Could not have a feature value.

   Specification

   InterfaceUsageDeclaration : InterfaceUsage =
         UsageDeclaration ValuePart?
         ( 'connect' InterfacePart )?
       | InterfacePart
   

   Old Implementation

   fragment InterfaceUsageDeclaration returns SysML::InterfaceUsage :
         UsageDeclaration? ( ConnectorKeyword InterfacePart )? 
       | InterfacePart
   ;
   

   Change. Added ValuePart? in first alternative.

6. RequirementConstraintUsage / FramedConcernUsage / ViewRenderingUsage – Disallowed declarations of the form assume c; to have a multiplicity (and similar for require, frame and render).

   Specification

   RequirementConstraintUsage : ConstraintUsage =
         ownedRelationship += OwnedReferenceSubsetting
         FeatureSpecializationPart? RequirementBody
       | ...
   
   FramedConcernUsage : ConcernUsage =
         ownedRelationship += OwnedReferenceSubsetting
         FeatureSpecializationPart? CalculationBody
       | ...
   
   ViewRenderingUsage : RenderingUsage =
         ownedRelationship += OwnedReferenceSubsetting
         FeatureSpecializationPart?
         UsageBody
       | ...
   

   Old Implementation

   RequirementConstraintUsage returns SysML::ConstraintUsage :
         ownedRelationship += OwnedReferenceSubsetting FeatureSpecialization* 
         CalculationBody
       | ...
   
   FramedConcernUsage returns SysML::ConcernUsage :
         ownedRelationship += OwnedReferenceSubsetting FeatureSpecialization* 
         RequirementBody
       | ...
   
   ViewRenderingUsage returns SysML::RenderingUsage :
         ownedRelationship += OwnedReferenceSubsetting FeatureSpecialization* UsageBody
       | ...
   

   Change. Changed FeatureSpecialization* to FeatureSpecializationPart?.

[himi]

Thank you for allowing me to review this important fix. I checked the grammar and found no issue. I'm still in Japan and cannot compile and check the code now this week. So please go ahead if you need.