QVT14 — [QVTr] Add CollectionTemplate comprehension content

ODM 1.0 uses a CollectionTemplate extension in which a collection comprehension is used to match Sequence content:

checkonly domain uml assn : Association{general = superassn : Association{
memberEnd = supSeq : Sequence(Property){usuper | true}},
memberEnd = subSeq : Sequence(Property){uprop | true}}

; // steps through both sequences in tandem

It is not clear how to achieve this without a CollectionTemnplate iterator.

The proposal for a co-iterator could avoid the guard and so allow

checkonly domain uml assn : Association{general = superassn : Association{
memberEnd = supSeq : Sequence(Property){usuper,index | true}},
memberEnd = subSeq : Sequence(Property){uprop,index | true}};