QVT13 — QVTc/QVTr: Imports

Concerning to Relations Language, how will the metamodels get into a transformation script ? Is there a technique similar to Operational Mappings using metamodel declaration and modeltypes ? The RL sample transformation script in annex A.1 (pp 164) doesn't declare the metamodels. The OM sample (A.2.3) does. There is some syntax for declaring and using metamodels and modeltypes in OM (pp118), there isn't for RL (pp38).

Relations Language: how will metamodels get into a transformation scrip

Concerning to Relations Language, how will the metamodels get into a transformation script ? Is there a technique similar to Operational Mappings using metamodel declaration and modeltypes ? The RL sample transformation script in annex A.1 (pp 164) doesn't declare the metamodels. The OM sample (A.2.3) does. There is some syntax for declaring and using metamodels and modeltypes in OM (pp118), there isn't for RL (pp38).

Discussion

We needs to support definition of e.g. UML in

transformation umlToRdbms(uml:UML, rdbms:RDBMS)

But we actually may want to reference a document URI or namespace URI

http://www.omg.org/spec/UML/20131001/UML.xmi
http://www.omg.org/spec/UML/20131001

But the current syntax is essentially a Java import without the trailing * option.

import my.model.package;

It cannot reference URIs and it has the wrong separator.

Something similar to QVTo's ModelType is needed:

modeltype UML uses SimpleUml ("http://omg.qvt-examples.SimpleUml");

However ModelType has many problems that we do not need to replicate:

• it is a Class; absolutely not
• it supports strict/effective inside rather than outside the program
• it has undefined URI usage

  Conversely Complrete OCL has a requirement for an import too, and here ModelType's are not appropriate at all.

Let's fix up import.