public static ReadModelUpdateResult <TReadModel> AsUnmodifedResult <TReadModel>(
     this ReadModelEnvelope <TReadModel> readModelEnvelope)
     where TReadModel : class, IReadModel
 {
     return(ReadModelUpdateResult <TReadModel> .With(
                readModelEnvelope,
                false));
 }
 public static ReadModelUpdateResult <TReadModel> AsModifedResult <TReadModel>(
     this ReadModelEnvelope <TReadModel> readModelEnvelope,
     TReadModel readModel,
     long?version = null)
     where TReadModel : class, IReadModel
 {
     return(ReadModelUpdateResult <TReadModel> .With(
                ReadModelEnvelope <TReadModel> .With(readModelEnvelope.ReadModelId, readModel, version),
                true));
 }