ResetFilters.scala

// Paw: List[Access[P]], where P is Orig, used in filters
  def resetFilters(defaultModelRegistry: DefaultModelRegistry, accesses: List[Access[_ <: Product]]): Context ⇒ Context = {
    val lambdas =
      for {
        access ← accesses
      } yield {
        val initValue = access.initialValue
        val srcId = ToPrimaryKey(initValue)
        val accessCl = initValue.getClass.getName
        val default = defaultModelRegistry.get(accessCl).create(srcId)
        access.updatingLens.get.set(default)
      }
    if (lambdas.nonEmpty)
      lambdas.reduce((a,b) ⇒ a andThen b)
    else
      identity
  }