QVT13 — Multiple input models

This is a suggestion:

A developer may need to take a set of in models that may vary in size each time he runs the transformation.

So, instead of hard-coding the input/out put models when defining the transformation like this:

transformation Uml2Rdbms(in uml:UML,out rdbms:RDBMS)

The developer should be able to define a dynamic set of input models. So that he will not be obligated to change the transformation definition if the number of input models change every time he runs the transformation.

For example, I defined a transformation that takes multiple input models (conforming to the same meta-model) to merge them. Now, I got different number of in models every time I run the transformation. To make this more dynamic, I need to take an array of models as an input to my transformation without specifying their numbers in the transformation definition each time I run the transformation.

Dynamic set of input models

This is a suggestion:

A developer may need to take a set of in models that may vary in size each time he runs the transformation.

So, instead of hard-coding the input/out put models when defining the transformation like this:

transformation Uml2Rdbms(in uml:UML,out rdbms:RDBMS)

The developer should be able to define a dynamic set of input models. So that he will not be obligated to change the transformation definition if the number of input models change every time he runs the transformation.

For example, I defined a transformation that takes multiple input models (conforming to the same meta-model) to merge them. Now, I got different number of in models every time I run the transformation. To make this more dynamic, I need to take an array of models as an input to my transformation without specifying their numbers in the transformation definition each time I run the transformation.

Discussion - imperative

This is already supported by the QVTo grammar. Just define a Collection of models as input or output.

transformation Uml2Rdbms(in uml:Sequence(UML),out rdbms:Sequence(RDBMS))

and use collection operations to access the individual models.

Discussion - declarative