Mapping of classes N to 1

Question

Hello,
I am still new to QVTo and learning.
I am trying to transform a model SRC to DST.
Description of the mapping:
The attributes from SRC:Block are being mapped to the DST:Blocks, DST:Diagram and DST:Props
While trying to map SRC class 'Block' to DST classes Blocks I have tried to constructors and intermediate classes (I have attached the ecore diagrams). However, I am getting errors while doing so. Kindly help.
The code I tried:
-- Declaration with a condition: the instance may differ from the metamodel,
-- but should have exactly one Project object. Location specific reference.
modeltype SRC uses "com.example.src" where
{ self.objectsOfType(Model)->size() = 1 };
-- Strict declaration, using a package namespace URI
modeltype DST "strict" uses "com.example.dst";
transformation SRCTransformation(in Source: SRC, out Target: DST);
main() {
Source.rootObjects()[Model] -> map ModelToSciMod();
constructor Props::Props (id:String,val: String) { Id:=id; Value:=val; }
mapping Model::ModelToSciMod(): SciMod {
Name := self.Name;
Version := "4.4";
-- objects:=self.newEReference ->new(x) Props(x.id, P()) ;
var s := self.newEReference ->map ObjToSys();
mapping Systems::ObjToSys(): Objects {
blocks:=self.blocks -> map BlkToBlk();
links:=self.links -> map LnToLn();
--constructor Props::Props (id:String,val: String) { Id:=id; Value:=val; }
constructor Diagram::Diagram (d:Props) { P:=d }
constructor Graphs::Graphs (att:Sequence(Props)) { }
mapping Block:: BlkToBlk(): Blocks {
Name:=self.Name;
var type:= self.BlockType;
var sid:= self.SID;
var ports:=self.Ports;
var prop1:= new Props("BlockType", type);
var prop2:= new Props("SID", sid);
var prop3:= new Props("Ports", ports);
var di := new Diagram(prop1) ;
dia:=intermediateDia -> map BlkToDia() ; -- ERROR showing here
intermediate class IntermediateBlk2 {
vars: OrderedSet(Block);
intermediate class IntermediateDia {
vars: OrderedSet(Block);
intermediate property IntermediateBlk2::intermediateDia :IntermediateDia ;
intermediate property IntermediateDia::intermediateP :Block ;
mapping IntermediateBlk2:: BlkToDia(): Diagram {
intermediateP
mapping Line:: LnToLn(): Links {
Kindly help.
Also, kindly let me know if there are any tutorials/reference documents explaining the keywords.
Thank you,
Abhishek

Answer 1

Hello Abhishek,
For documentation about QVTo check the WIKI:
https://wiki.eclipse.org/QVTo
Especially the EclipseCon 2009 presentation.
If you want a complete overview off all keywords, check the QVTo specification.
http://www.omg.org/spec/QVT/1.2/PDF/
If you want help with your error, please list the error as well. Also providing minimal examples of your problem in your question instead of listing everything will help in getting answers.
As a start, adding intermediate properties to intermediate classes is strange (and maybe not well supported by the implementation). Add those attributes directly to the intermediate class.