SYSML2_ — Definitions of View Usage are Too Restricted

View usage is restricted to have at most one definition which must be a view definition:

      /viewDefinition : ViewDefinition [0..1] {redefines partDefinition}

With this passage viewDefinition field redefines partDefinition field - this makes constraints on what partDefinition field values can be - namely (at most) one definition which must be a view definition.

This is too restrictive and precludes some valid use cases; For example, additional "instrumentation" of the view with additional properties to implement diagram properties
e.g.:

part def VendorSpecificDiagramProperties {
   attribute showGrid:Boolean;
   //other diagram style attributes here
}
//.......
view usage usersDiagram: InterconnectionView, VendorSpecificDiagramProperties {
 :>>showGrid = true;
}

This restriction could be relaxed to e.g. viewDefinition subsetting partDefinition instead of redefining, allowing more flexible use of views (just like partDefinition only subsets itemDefinition).

Defer to RTF

This issue was submitted after the end of the comment period, and the FTF has decided to defer its consideration to a future RTF.