modularize Banana appplication with traits; need of examples

Hi all

All of the Banana tests use classes , not traits.
However, the best practice for modularizing with Scala seems to use traits.

The Banana documentation is geared towards people extending the framework
e.g. for adding support to new RDF engines.
But there is not really a documentation oriented toward appplication
developers.

And the only open source Banana applications are mine, so there is no other
source of inspiration.
Does this mean that Banana is only for the beauty of the code ?
I don't think so !

This being said,
here is a short trait that is not compiling.
In the last mounths,
I tried several designs, but I was not able to find some design patterns
for Banana with traits.

The compile message is:
type mismatch; found : query.type (with underlying type
TestTrait.this.Rdf#ConstructQuery) required: Rdf#ConstructQuery

And the code :

package deductions.runtime.services

import scala.util.Try
import org.w3.banana.RDF
import org.w3.banana.RDFOps
import org.w3.banana.RDFStore
import org.w3.banana.SparqlEngine
import org.w3.banana.SparqlOps
import org.w3.banana.syntax._
import org.w3.banana.SparqlOpsModule

trait RDFStoreLocalProvider[Rdf <: RDF, DATASET] {
  implicit val rdfStore: RDFStore[Rdf, Try, DATASET]
  val dataset: DATASET
}

trait TestTrait[Rdf <: RDF, DATASET]
    extends RDFStoreLocalProvider[Rdf, DATASET]
    with SparqlOpsModule {

  implicit val ops: RDFOps[Rdf]
  val queryString = s"""
         |CONSTRUCT { ?thing ?p ?o } WHERE {
         |  graph ?g {
         |    ?thing ?p ?o .
         |    FILTER regex( ?o, "search", 'i')
         |  }
         |}""".stripMargin

  import ops._
  import sparqlOps._
  import rdfStore.sparqlEngineSyntax._

  def lookup(search: String) = {
    val graph =
      for {
        query <- parseConstruct(queryString)
        es <- dataset.executeConstruct(query, Map()) // ERROR
      } yield es
    val triples = ops.getTriples(graph) // ERROR
  }
}


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