public Task <IActionResult> HandleDeleteConfirmedAsync(
     Action <TEntity> setPageEntity,
     Func <TUserContext, bool> authorize,
     string formEntityPrefix,
     Func <TEntity> constructor,
     Dictionary <string, Func <TEntity, Action <StringValues> > > hiddenFormFields
     ) =>
 HandlePageSaveAsync(setPageEntity, pageRoutineFeature,
                     (repository, closure) => steps =>
                     steps(
                         () => authorize?.Invoke(closure.UserContext) ?? true,
                         request => MvcHandler.Bind(request, formEntityPrefix, constructor,
                                                    // TODO: convert to Empty instance
                                                    new Dictionary <string, Func <TEntity, Func <StringValues, IVerboseResult <List <string> > > > >(),
                                                    hiddenFormFields),
                         (entity, batch) => batch.Remove(entity)
                         )
                     );
 public Task <IActionResult> HandleCreateConfirmedAsync(
     Action <TEntity> setPageEntity,
     Func <TUserContext, bool> authorize,
     string formEntityPrefix,
     Func <TEntity> constructor,
     Dictionary <string, Func <TEntity, Func <StringValues, IVerboseResult <List <string> > > > > formFields,
     Dictionary <string, Func <TEntity, Action <StringValues> > > hiddenFormFields,
     Func <Action <string, object>, HttpRequest, IRepository <TEntity>, TEntity, IComplexBinderResult <ValueTuple <Action <IBatch <TEntity> >, Action> > > parseRelated
     ) =>
 HandlePageSaveAsync(setPageEntity, pageRoutineFeature,
                     (repository, closure) => steps =>
                     steps(
                         () => authorize?.Invoke(closure.UserContext) ?? true,
                         request => MvcHandler.Bind(request, formEntityPrefix, constructor, formFields, hiddenFormFields),
                         (request, entity, addViewData) => parseRelated(addViewData, request, repository, entity),
                         (entity, batch) => batch.Add(entity)
                         )
                     );