MDG extend _subtypeProperty to support multiple tagged values

[Guillaume]

_subtypeProperty is a specific attribute to use in stereotypes/MDG definition so the user is prompted to select a value from a list to set the tagged value when created e.g. type = A, B, C.
EA provides this behaviour when creating BPMN 2 Gateways

According to this thread (https://sparxsystems.com/forums/smf/index.php?topic=4890.0) this is limited to a single tagged value.
Would it be possible to add a support for multiple tagged values? For instance I have stereotyped SysML Ports and would like to prompt the user to select a Type and the Direction upon creation from the toolbox.
I think this could be achieved by supporting ";" delimited values in the _subtypeProperty metaclass attribute, or by adding suffixes on _subtypeProperty  (_subtypeProperty ,_subtypeProperty1, _subtypeProperty2...)

_subtypeProperty = MyProfile::MyPort::type;MyProfile::MyPort::direction
with type and direction available as enum tagged values

Guillaume