make it possible to not update the view at all after onRefresh/confict...

make it possible to not update the view at all after onRefresh/confict resolution of interaction tasks

Examples/Applications/Incidone/Incidone/ActionManagementTasks.icl

@@ -670,7 +670,7 @@ updateActionStatus current = withShared current
         -|| (Hint "Incidents:"  @>> updateSharedIncidentRefList True (incidents updating))
         ) <<@ (Title "Update action")
 where
-    updateMeta status = updateSharedInformation [UpdateSharedAs toPrj fromPrj const] status
+    updateMeta status = updateSharedInformation [UpdateSharedAs toPrj fromPrj (const o Just)] status
     where
         toPrj {ActionStatus|title,description} = {ItemMeta|title=title,description=description}
         fromPrj status {ItemMeta|title,description} = {ActionStatus|status & title=title,description=description}

Examples/Applications/Incidone/Incidone/DeviceBased/Tablet.icl

@@ -30,7 +30,7 @@ where
             = get (standardMapLayers |*| standardPerspective)
             >>- \(baseLayers,perspective) ->
                 withShared perspective
-                \p -> Title title @>> updateSharedInformation [UpdateSharedAs (toMap baseLayers) fromMap const] (p >*| mapContacts) @ fst
+                \p -> Title title @>> updateSharedInformation [UpdateSharedAs (toMap baseLayers) fromMap (const o Just)] (p >*| mapContacts) @ fst
             //<<@ AfterLayout (tweakUI fill) //FIXME
             @   WallOverview
         where

Examples/Applications/Incidone/Incidone/Extensions/CrewLists.icl

@@ -55,7 +55,7 @@ where
     refs = sdsFocus contactNo crewAliasListsStore
 
     manageCurrentItems
-        = Hint "Manage crew list" @>> updateSharedInformation [UpdateSharedAs toPrj fromPrj const] items
+        = Hint "Manage crew list" @>> updateSharedInformation [UpdateSharedAs toPrj fromPrj (const o Just)] items
     where
         items = sdsDeref refs snd contactsByNosShort derefAliasList
         toPrj l = [(contactIdentity c, aNo, contactTitle c)\\(aNo,c) <-l]

Examples/Applications/Incidone/Incidone/OP/ContactManagementTasks.icl

@@ -397,9 +397,9 @@ updateContactPosition contactNo
     >>- \({Contact|name,type,position},baseLayers) ->
         withShared (position,initPerspective position)
         \tmpInfo ->
-        (Title "Position update" @>> Hint ("Update position of contact "<+++ name) @>> updateSharedInformation [UpdateSharedAs fst (\(_,y) x -> (x,y)) const] tmpInfo
+        (Title "Position update" @>> Hint ("Update position of contact "<+++ name) @>> updateSharedInformation [UpdateSharedAs fst (\(_,y) x -> (x,y)) (const o Just)] tmpInfo
          -||-
-         updateSharedInformation [UpdateSharedAs (toMap baseLayers) (fromMap baseLayers) const] tmpInfo
+         updateSharedInformation [UpdateSharedAs (toMap baseLayers) (fromMap baseLayers) (const o Just)] tmpInfo
          -||-
           (Hint "Search the web" @>> viewSharedInformation  [ViewAs (toSearchURLs o fst)] tmpInfo)
         ) @ fst
@@ -446,7 +446,7 @@ updateSharedContactRefList refs
     >^* [OnAction (Action "Add") (always (addItem <<@ InWindow))]
 where
     manageCurrentItems
-        = updateSharedInformation [UpdateSharedAs toPrj fromPrj const] items @ map contactIdentity
+        = updateSharedInformation [UpdateSharedAs toPrj fromPrj (const o Just)] items @ map contactIdentity
     where
         items = sdsDeref refs id contactsByNosShort (\_ cs -> cs)
         toPrj l = [(contactIdentity c,contactTitle c) \\ c <-l]
@@ -564,9 +564,9 @@ viewContactsOnMap sharedContacts sel
    >>- \(baseLayers,perspective) ->
        withShared (False,perspective)
        \localState ->
-            Hint "Show AIS contacts:" @>> updateSharedInformation [UpdateSharedAs fst (\(_,y) x -> (x,y)) const] localState
+            Hint "Show AIS contacts:" @>> updateSharedInformation [UpdateSharedAs fst (\(_,y) x -> (x,y)) (const o Just)] localState
             ||-
-            (updateSharedInformation [UpdateSharedAs (toPrj baseLayers) fromPrj const] (mapState localState sharedContacts sel)) @ (\(a,b,c) -> (b,c))
+            (updateSharedInformation [UpdateSharedAs (toPrj baseLayers) fromPrj (const o Just)] (mapState localState sharedContacts sel)) @ (\(a,b,c) -> (b,c))
             >^* [OnAction (Action "/Share map to wall") (hasValue sharePerspective)
                 ]
         @? selection

Examples/Applications/Incidone/Incidone/OP/IncidentManagementTasks.icl

@@ -172,7 +172,7 @@ updateSharedIncidentRefList compact refs
     >^* [OnAction (Action "Add") (always (addItem <<@ InWindow))]
 where
     manageCurrentItems
-        = updateSharedInformation [UpdateSharedAs toPrj fromPrj const] items @ map incidentIdentity
+        = updateSharedInformation [UpdateSharedAs toPrj fromPrj (const o Just)] items @ map incidentIdentity
     where
         items = sdsDeref refs id incidentsByNosShort (\_ is -> is)
         toPrj l = [(incidentIdentity i,incidentTitle i) \\i <-l]

Examples/Applications/Incidone/Incidone/RoleBased/AdministratorTasks.icl

@@ -229,7 +229,7 @@ configureMaps
 where
     previewMapLayers :: Task ContactMapPerspective
     previewMapLayers = withShared defaultValue
-        \perspective -> (Title "Preview" @>> updateSharedInformation [UpdateSharedAs toPrj fromPrj const] (perspective >*| standardMapLayers)) <<@ ApplyLayout flexMap @ fst
+        \perspective -> (Title "Preview" @>> updateSharedInformation [UpdateSharedAs toPrj fromPrj (const o Just)] (perspective >*| standardMapLayers)) <<@ ApplyLayout flexMap @ fst
     where
         toPrj (perspective,layers) = toLeafletMap {ContactMap|defaultValue & perspective=perspective,layers=layers}
         fromPrj _ {LeafletMap|perspective} = fromLeafletPerspective perspective

Examples/Applications/ShipAdventure/C2/Apps/ShipAdventure/Core.icl

@@ -62,7 +62,7 @@ actorWithInstructions user
   pickStartRoom :: Task Coord3D
   pickStartRoom
     = Hint "Which room do you want to start in?" @>> updateInformationWithShared 
-        [UpdateSharedUsing id (const snd) const editor]
+        [UpdateSharedUsing id (const snd) (const o Just) editor]
         (maps2DShare |*| myNetwork) NoAction
     >>* [OnValue (\v -> case v of
                           Value (FocusOnSection c3d) _ = Just (return c3d)
@@ -387,7 +387,7 @@ mkSection :: MyDrawMapForActor
 mkSection
   = \user shStatusMap shUserActor shSectionInventoryMap ->
       Title "Section Status" @>> updateSharedInformation 
-		  [UpdateSharedUsing id (\_ _ -> ()) const editor]
+		  [UpdateSharedUsing id (\_ _ -> ()) (const o Just) editor]
           (sectionForUserShare user |*| myNetwork |*| myDevices |*| shStatusMap |*| sectionUsersShare |*| myUserActorMap |*| shSectionInventoryMap |*| lockedExitsShare |*| lockedHopsShare |*| maps2DShare)
           @! ()
   where

Examples/Applications/ShipAdventure/C2/Apps/ShipAdventure/Editor.icl

@@ -184,7 +184,7 @@ intMapCrudWith descr cos eos vos uos mkId share = Title descr @>> crudWith cos e
 graphicalMapEditor :: Task ()
 graphicalMapEditor
   = Title "Graphical map editor" @>> updateSharedInformation 
-      [UpdateSharedUsing id (const fst) const imageEditor]
+      [UpdateSharedUsing id (const fst) (const o Just) imageEditor]
       (sharedEditShip >*| (myInventoryMap |*| myNetwork |*| myDevices)) @! ()
 	  @! ()
 where
@@ -199,8 +199,8 @@ where
 editLayout :: Task ()
 editLayout
   = allTasks [ graphicalMapEditor
-             , Title "Edit map dimensions" @>> updateSharedInformation  [UpdateSharedAs toMapsForm fromMapsForm const] maps2DShare @! ()
-             , Title "Edit map" @>> updateSharedInformation [UpdateSharedAs toMapActionForm fromMapActionForm const] sharedEditShip @! ()
+             , Title "Edit map dimensions" @>> updateSharedInformation  [UpdateSharedAs toMapsForm fromMapsForm (const o Just)] maps2DShare @! ()
+             , Title "Edit map" @>> updateSharedInformation [UpdateSharedAs toMapActionForm fromMapActionForm (const o Just)] sharedEditShip @! ()
              , (watch maps2DShare
                -&&- (Title "Quick borders" @>> enterChoiceWithShared [] (mapRead (\ship -> [mapId \\ {Map2D | mapId} <- ship]) maps2DShare))
                >>* [ OnAction (Action "Add outer borders"    ) (hasValue (uncurry (editOuterBorders Wall)))
@@ -249,7 +249,7 @@ editSectionContents :: Task ()
 editSectionContents
   = allTasks [ graphicalMapEditor
              , withSelectedSection (
-                 \mid c2d -> (Title (mkDesc mid c2d "Inventory"))  @>> updateSharedInformation [UpdateSharedAs fromInv toInv const] (sdsFocus (mid, c2d) inventoryInSectionShare)
+                 \mid c2d -> (Title (mkDesc mid c2d "Inventory"))  @>> updateSharedInformation [UpdateSharedAs fromInv toInv (const o Just)] (sdsFocus (mid, c2d) inventoryInSectionShare)
                )
              , withSelectedSection (
                  \mid c2d -> let focusedShare = sdsFocus (mid, c2d) devicesInSectionShare

Examples/Applications/ShipAdventure/C2/Apps/ShipAdventure/Types.icl

@@ -420,7 +420,7 @@ updateMapStatus mode
                           Value x _ -> Just x
                           _         -> Nothing) sharedMapAction */
       (Title "Map Status" @>> updateInformationWithShared 
-        [UpdateSharedUsing id (const snd) const editor]
+        [UpdateSharedUsing id (const snd) (const o Just) editor]
         (disabledSections |*| maps2DShare |*| lockedExitsShare |*| lockedHopsShare |*| myInventoryMap |*| myStatusMap |*| sectionUsersShare |*| myUserActorMap |*| myNetwork |*| myDevices)
         NoAction)
 where
@@ -437,7 +437,7 @@ disabledSections = sharedStore "disabledSections" 'DS'.newSet
 updateSectionStatus :: !Coord3D -> Task (MapAction SectionStatus)
 updateSectionStatus c3d=:(floorIdx, _)
   = Title "Section Status" @>> updateInformationWithShared 
-      [UpdateSharedUsing id (const snd) const editor]
+      [UpdateSharedUsing id (const snd) (const o Just) editor]
       (maps2DShare |*| lockedExitsShare |*| lockedHopsShare |*| sdsFocus c3d inventoryInSectionShare |*| sdsFocus c3d statusInSectionShare |*| sdsFocus c3d (actorsInSectionShare myUserActorMap) |*| myNetwork |*| myDevices)
       NoAction
 where

Examples/Applications/ShipAdventure/C2/Framework/Common.icl

@@ -80,7 +80,7 @@ periodicallyUpdateEntity :: !Int -> Task ()
 periodicallyUpdateEntity n = updateEntity n moveEntity // TODO FIXME PERFORMANCE doTaskPeriodically 1 (updateEntity n moveEntity) <<@ NoUserInterface
 
 mapView` :: User [Entity] -> Task ()
-mapView` currentUser es = (updateSharedInformation [UpdateSharedAs toMap fromMap const] (userMapState currentUser >*< entityMap) @! ())
+mapView` currentUser es = (updateSharedInformation [UpdateSharedAs toMap fromMap (const o Just)] (userMapState currentUser >*< entityMap) @! ())
   where
   toMap :: (MapState, EntityMap) -> LeafletMap
   toMap ({MapState | perspective}, markers)
@@ -106,7 +106,7 @@ mapView` currentUser es = (updateSharedInformation [UpdateSharedAs toMap fromMap
 
 
 mapView :: (sds () r w) (r -> Bool) User [Entity] -> Task () | iTask r & iTask w & RWShared sds
-mapView sh radarWorks currentUser es = (updateSharedInformation [UpdateSharedAs toMap fromMap const] (mapState >*| sh) @! ())
+mapView sh radarWorks currentUser es = (updateSharedInformation [UpdateSharedAs toMap fromMap (const o Just)] (mapState >*| sh) @! ())
   where
   toMap ({perspective, entities = markers}, shval)
     = toLeafletMap { ContactMap

Examples/BasicAPIExamples/InteractionUsingShares/SharedNoteAsList.icl

@@ -23,5 +23,5 @@ where
 		>>=		\result -> Hint "Result:" @>> viewInformation [] result
 		>>=		return
 
-	noteEditor = UpdateSharedUsing id (const id) const textArea
-	listEditor = UpdateSharedAs (split "\n") (\_ l -> join "\n" l) const
+	noteEditor = UpdateSharedUsing id (const id) (const o Just) textArea
+	listEditor = UpdateSharedAs (split "\n") (\_ l -> join "\n" l) (const o Just)

Examples/BasicAPIExamples/InteractionUsingShares/SharedNotes.icl

@@ -20,11 +20,10 @@ sharedNotes
 			(Hint "View on note" @>> viewSharedInformation [ViewUsing id textArea] note)
 			-||-
 			// an editor to update the shared string
-			((Hint "Update shared note 1" @>> updateSharedInformation [UpdateSharedUsing id (const id) const textArea] note)	
+			((Hint "Update shared note 1" @>> updateSharedInformation [UpdateSharedUsing id (const id) (const o Just) textArea] note)
 			  -||-
 			// and an other updating editor
-			 (Hint "Update shared note 2" @>> updateSharedInformation [UpdateSharedUsing id (const id) const textArea] note)	
-					 		
+			 (Hint "Update shared note 2" @>> updateSharedInformation [UpdateSharedUsing id (const id) (const o Just) textArea] note)
 			) <<@ ArrangeHorizontal 
 		)
 	>>= \result -> Hint "Resulting string is:" @>> viewInformation [ViewUsing id textArea] result

Examples/BasicAPIExamples/ParallelExamples/TinyTextEditor.icl

@@ -34,7 +34,7 @@ editWithStatistics
 
 editFile :: String (Shared sds String)  -> Task () | RWShared sds
 editFile fileName sharedFile
-	= Hint ("edit " +++ fileName) @>> updateSharedInformation [UpdateSharedUsing id (const id) const textArea] sharedFile @! ()
+	= Hint ("edit " +++ fileName) @>> updateSharedInformation [UpdateSharedUsing id (const id) (const o Just) textArea] sharedFile @! ()
 
 showStatistics :: (Shared sds String) -> Task () | RWShared sds
 showStatistics sharedFile = Hint "Statistics:" @>> viewSharedInformation [ViewAs stat] sharedFile @! ()

Examples/BasicAPIExamples/SequentialExamples/CalculateSumInShare.icl

@@ -20,6 +20,6 @@ calculateSumInRecord
   = 				withShared (0,0)
   (\sum ->			Title "Sum of 2 numbers, with view" @>> updateSharedInformation
   						[UpdateSharedAs (\(i,j) -> {firstNumber = i, secondNumber = j, sum = (i+j)})
-  						          (\_ res -> (res.firstNumber,res.secondNumber)) const] sum
+  						          (\_ res -> (res.firstNumber,res.secondNumber)) (const o Just)] sum
   )
   >>= \(i,j) ->		return (i+j)

Examples/GIS/LeafletMapExample.icl

@@ -14,7 +14,7 @@ playWithMaps = withShared ({defaultValue & icons = shipIcons},defaultValue) (\m
 
 derive gDefault LeafletSimpleState, LeafletObjectID
 manipulateMap :: (Shared sds (LeafletMap,LeafletSimpleState)) -> Task () | RWShared sds
-manipulateMap m = updateSharedInformation [UpdateSharedUsing id (flip const) const (customLeafletEditor eventHandlers defaultValue)] m
+manipulateMap m = updateSharedInformation [UpdateSharedUsing id (flip const) (const o Just) (customLeafletEditor eventHandlers defaultValue)] m
 	<<@ ApplyLayout (setUIAttributes (sizeAttr FlexSize FlexSize)) @! ()
 where
 	eventHandlers = {simpleStateEventHandlers & onHtmlEvent = onHtmlEvent}

Examples/Games/Ligretto/Ligretto/UI.icl

 implementation module Ligretto.UI
 
 import StdBool, StdEnum, StdList
-from   StdFunc import id, const
+from   StdFunc import id, const, o
 import Data.GenEq
 import iTasks.WF.Tasks.Interaction
 import Graphics.Scalable.Extensions
@@ -9,14 +9,14 @@ import iTasks.Extensions.SVG.SVGEditor
 import Ligretto.UoD
 
 ligrettoEditor :: !Color -> UpdateSharedOption GameSt GameSt
-ligrettoEditor me = UpdateSharedUsing id (const id) const (fromSVGEditor
+ligrettoEditor me = UpdateSharedUsing id (const id) (const o Just) (fromSVGEditor
 												{ initView    = id
 												, renderImage = const (player_perspective me)
 												, updModel    = const id
 												})
 
 accoladesEditor :: !Color -> UpdateSharedOption GameSt GameSt
-accoladesEditor me = UpdateSharedUsing id (const id) const (fromSVGEditor
+accoladesEditor me = UpdateSharedUsing id (const id) (const o Just) (fromSVGEditor
 												{ initView    = id
 												, renderImage = const (player_perspective me)
 												, updModel    = const id

Examples/Games/Trax/Trax/UI.icl

 implementation module Trax.UI
 
 import StdBool, StdList
-from   StdFunc import const, flip, id
+from   StdFunc import const, flip, id, o
 from   Data.List import lookup
 import iTasks.WF.Tasks.Interaction
 import iTasks.Extensions.SVG.SVGEditor
@@ -10,7 +10,7 @@ import Trax.UoD
 :: RenderMode = ViewMode | PlayMode
 
 updateTraxEditor :: Bool -> UpdateSharedOption TraxSt TraxSt
-updateTraxEditor turn 				= UpdateSharedUsing id (const id) const (fromSVGEditor
+updateTraxEditor turn 				= UpdateSharedUsing id (const id) (const o Just) (fromSVGEditor
 													{ initView    = id
 													, renderImage = \_ -> toImage PlayMode turn
 													, updModel    = flip const

Libraries/iTasks/Util/Testing.icl

@@ -83,7 +83,7 @@ filterTestsByName pattern tests = filter (\{UnitTest|name} -> indexOf pattern na
 //UTILITY TASKS
 testEditor :: (Editor a) (EditMode a) -> Task a | iTask a
 testEditor editor mode
-	=   (interactR unitShare {onInit = const ((),mode), onEdit = \v l -> (l,Nothing), onRefresh = \_ l (Just v) -> (l,v,Nothing)} editor @ snd
+	=   (interactR unitShare {onInit = const ((),mode), onEdit = \v l -> (l,Nothing), onRefresh = \_ l v -> (l,v,Nothing)} editor @ snd
 	>&> \s -> Title "Editor value" @>> viewSharedInformation [ViewAs (toString o toJSON)] s @? tvFromMaybe
 	)  <<@ ArrangeHorizontal
 
@@ -94,7 +94,7 @@ testEditorWithShare editor model viewMode = (withShared model
 		||-
 	    (Title "Editor under test" @>> interactR smodel {onInit = \r -> ((),if viewMode View Update $ r)
 	                                        ,onEdit = \v l -> (l,Just (\_ -> v))
-	                                        ,onRefresh = \r l v -> (l,r,Nothing)} editor @ snd)
+	                                        ,onRefresh = \r l _ -> (l,Just r,Nothing)} editor @ snd)
 	) <<@ ArrangeHorizontal
 
 testCommonInteractions :: String -> Task a | iTask, gDefault{|*|} a

Libraries/iTasks/WF/Tasks/Core.dcl

@@ -76,7 +76,7 @@ instance toString OSException
 :: InteractionHandlers l r w v =
     { onInit    :: !(r -> (l, EditMode v))
     , onEdit    :: !(v l -> (l, Maybe (r -> w)))
-    , onRefresh :: !(r l (Maybe v) -> (l, v, Maybe (r -> w)))
+    , onRefresh :: !(r l (Maybe v) -> (l, Maybe v, Maybe (r -> w)))
 	}
 
 //Version which can write shared data

Libraries/iTasks/WF/Tasks/Core.icl

@@ -154,8 +154,12 @@ evalInteract l v mst mode sds handlers editor writefun event=:(RefreshEvent task
 	| 'DS'.member taskId taskIds
 		= readRegisterCompletely sds (maybe NoValue (\v->Value (l, v) False) v) (\e->mkUIIfReset e (asyncSDSLoaderUI Read))
 			(\r event evalOpts iworld
-				# (l, v, mbf) = handlers.InteractionHandlers.onRefresh r l v
-				= case withVSt taskId (editor.Editor.onRefresh [] v (fromJust mst)) iworld of
+				# (l, mbV, mbf) = handlers.InteractionHandlers.onRefresh r l v
+				# st            = fromJust mst
+				# mbChange = case mbV of
+					Just v  = withVSt taskId (editor.Editor.onRefresh [] v (fromJust mst)) iworld
+					Nothing = (Ok (NoChange, st), iworld)
+				= case mbChange of
 					(Error e, iworld) = (ExceptionResult (exception e), iworld)
 					(Ok (change, st), iworld)
 						# v = editor.Editor.valueFromState st

Libraries/iTasks/WF/Tasks/Interaction.dcl

@@ -25,11 +25,12 @@ from Data.Functor import class Functor
 //When both the view has been edited, and the sds has changed, this
 //function determines what the new view should be.
 //The first argument is the new view as computed from the changed sds,
-//and the second argument is the edited view by the user.
+//and the second argument is the edited view by the user, if the current view represents a valid value.
+//If the result is `Nothing` the view is not updated.
 :: UpdateSharedOption a b 
-	= E.v: UpdateSharedAs (a -> v) (a v -> b) (v (Maybe v) -> v) & iTask v
-	| E.v: UpdateSharedUsing (a -> v) (a v -> b) (v (Maybe v) -> v) (Editor v) & iTask v
-	| E.v: UpdateSharedUsingAuto (a -> Maybe v) (a v -> b) (v (Maybe v) -> v) (Editor v) & iTask v
+	= E.v: UpdateSharedAs (a -> v) (a v -> b) (v (Maybe v) -> Maybe v) & iTask v
+	| E.v: UpdateSharedUsing (a -> v) (a v -> b) (v (Maybe v) -> Maybe v) (Editor v) & iTask v
+	| E.v: UpdateSharedUsingAuto (a -> Maybe v) (a v -> b) (v (Maybe v) -> Maybe v) (Editor v) & iTask v
 
 //Selection in arbitrary containers (explicit identification is needed)
 :: SelectOption c s

Libraries/iTasks/WF/Tasks/Interaction.icl

@@ -52,7 +52,7 @@ updateSharedEditor :: [UpdateSharedOption r w] -> UpdateSharedOption r w | iTask
 updateSharedEditor [UpdateSharedUsing tof fromf conflictf editor:_] = UpdateSharedUsing tof fromf conflictf editor
 updateSharedEditor [UpdateSharedAs tof fromf conflictf:_] = UpdateSharedUsing tof fromf conflictf gEditor{|*|}
 updateSharedEditor [_:es] = updateSharedEditor es
-updateSharedEditor [] =  UpdateSharedUsingAuto dynid (flip const) const gEditor{|*|}
+updateSharedEditor [] =  UpdateSharedUsingAuto dynid (flip const) (const o Just) gEditor{|*|}
 where
 	//If r == w then this is just the identity, otherwise the editor will use a default value
 	dynid x = case dynamic id :: A.a: (a -> a) of
@@ -102,12 +102,12 @@ where
 viewInformation :: ![ViewOption m] !m -> Task m | iTask m
 viewInformation options m = viewInformation`  (viewEditor options) m
 viewInformation` (ViewUsing tof editor) m
-	= interactR unitShare {onInit = const ((),View $ tof m), onEdit = \_ l -> (l, Nothing), onRefresh = \r l (Just v) -> (l,v,Nothing)} editor @! m
+	= interactR unitShare {onInit = const ((),View $ tof m), onEdit = \_ l -> (l, Nothing), onRefresh = \r l v -> (l,v,Nothing)} editor @! m
 
 updateInformation :: ![UpdateOption m] m -> Task m | iTask m
 updateInformation options m = updateInformation` (updateEditor options) m
 updateInformation` (UpdateUsing tof fromf editor) m
-	= interactRW unitShare {onInit = const ((), Update $ tof m), onEdit = \_ l -> (l, Nothing), onRefresh = \r l (Just v) -> (l,v,Nothing)}
+	= interactRW unitShare {onInit = const ((), Update $ tof m), onEdit = \_ l -> (l, Nothing), onRefresh = \r l v -> (l,v,Nothing)}
 		editor @ (\((),v) -> fromf m v)
 
 updateSharedInformation :: ![UpdateSharedOption r w] !(sds () r w) -> Task r | iTask r & iTask w & RWShared sds
@@ -117,13 +117,13 @@ updateSharedInformation` (UpdateSharedUsing tof fromf conflictf editor) sds
 		editor @ fst
 updateSharedInformation` (UpdateSharedUsingAuto tof fromf conflictf editor) sds
 	= interactRW sds {onInit = \r -> (r, maybe Enter Update (tof r)), onEdit = \v l -> (l, Just (\r -> fromf r v))
-			, onRefresh = \r _ v -> (r, maybe undef (\r` -> conflictf r` v) (tof r), Nothing)}
+			, onRefresh = \r _ v -> (r, maybe Nothing (\r` -> conflictf r` v) (tof r), Nothing)}
 		editor @ fst
 
 viewSharedInformation :: ![ViewOption r] !(sds () r w) -> Task r | iTask r & TC w & Registrable sds
 viewSharedInformation options sds = viewSharedInformation` (viewEditor options) sds
 viewSharedInformation` (ViewUsing tof editor) sds
-	= interactR sds {onInit = \r -> (r, View $ tof r), onEdit = \_ l -> (l, Nothing), onRefresh = \r _ _ -> (r,tof r,Nothing)} editor @ fst
+	= interactR sds {onInit = \r -> (r, View $ tof r), onEdit = \_ l -> (l, Nothing), onRefresh = \r _ _ -> (r,Just $ tof r,Nothing)} editor @ fst
 
 updateInformationWithShared :: ![UpdateSharedOption (r,m) m] !(sds () r w) m -> Task m | iTask r & iTask m & TC w & RWShared sds
 updateInformationWithShared options sds m = updateInformationWithShared` (updateSharedEditor options) sds m
@@ -131,7 +131,7 @@ updateInformationWithShared` (UpdateSharedUsing tof fromf conflictf editor) sds
 	= interactRW sds
 		{onInit = \r -> ((r,m), Update $ tof (r,m))
 		,onEdit = \v (r,m)      -> let nm = fromf (r,m) v in ((r,nm),Nothing)
-		,onRefresh = \r (_,m) _ -> ((r,m),tof (r,m),Nothing)
+		,onRefresh = \r (_,m) _ -> ((r,m),Just $ tof (r,m),Nothing)
 		} gEditor{|*|} @ (snd o fst)
 
 editSelection :: ![SelectOption c a] c [Int] -> Task [a] | iTask a
@@ -140,7 +140,7 @@ editSelection` attributes (SelectUsing toView fromView editor) container sel
 	= interactRW unitShare
 		{onInit = \r   -> ((), Update (toView container,sel))
 		,onEdit = \_ l -> (l, Nothing)
-		,onRefresh = \_ l (Just v) -> (l,v,Nothing)
+		,onRefresh = \_ l v -> (l,v,Nothing)
 		} (attributes @>> editor) @ (\(_,(_,sel)) -> fromView container sel)
 
 editSelectionWithShared :: ![SelectOption c a] (sds () c w) (c -> [Int]) -> Task [a] | iTask c & iTask a & TC w & RWShared sds
@@ -149,7 +149,7 @@ editSelectionWithShared` attributes (SelectUsing toView fromView editor) sharedC
 	= interactRW sharedContainer
 		{onInit = \r     -> (r, Update(toView r, initSel r))
 		,onEdit = \_ l -> (l, Nothing)
-		,onRefresh = \r l (Just (v,sel)) -> (r,(toView r,sel),Nothing)
+		,onRefresh = \r l v -> (r,(\(_, sel) -> (toView r,sel)) <$> v,Nothing)
 		} (attributes @>> editor) @ (\(container,(_,sel)) -> fromView container sel)
 
 editSharedSelection :: ![SelectOption c a] c (Shared sds [Int]) -> Task [a] | iTask c & iTask a & RWShared sds
@@ -158,7 +158,7 @@ editSharedSelection` attributes (SelectUsing toView fromView editor) container s
 	= interactRW sharedSel
 		{onInit = \r        -> ((), Update (toView container,r))
 		,onEdit = \(_,vs) l -> (l, Just (const vs))
-		,onRefresh = \r l (Just (vt,vs)) -> (l,(vt,r),Nothing)
+		,onRefresh = \r l v -> (l,(\(vt, _) -> (vt, r)) <$> v,Nothing)
 		} (attributes @>> editor) @ (\(_,(_,sel)) -> fromView container sel)
 
 editSharedSelectionWithShared :: ![SelectOption c a] (sds1 () c w) (Shared sds2 [Int]) -> Task [a] | iTask c & iTask a & TC w & RWShared sds1 & RWShared sds2
@@ -168,7 +168,7 @@ editSharedSelectionWithShared` attributes (SelectUsing toView fromView editor) s
 	= interactRW (sharedContainer |*< sharedSel)
 		{onInit = \(rc, rs)  -> (rc, Update (toView rc,rs))
 		,onEdit = \(_, vs) l -> (l, Just (const vs))
-		,onRefresh = \(rc, rs)   _ _ -> (rc, (toView rc, rs), Nothing)
+		,onRefresh = \(rc, rs)   _ _ -> (rc, Just (toView rc, rs), Nothing)
 		} (attributes @>> editor) @ (\(container, (_, sel)) -> fromView container sel)
 
 //Core choice tasks

Tests/Interactive/TaskPatterns/TestMultipleViewsOnSDS.icl

@@ -18,8 +18,8 @@ editInTextArea model
 editAsListOfLines model
 	=   Title "Lines" @>> Hint "Edit lines" @>> updateSharedInformation [listEditor] model
 
-noteEditor = UpdateSharedUsing id (const id) const textArea
-listEditor = UpdateSharedAs (split "\n") (\_ l -> join "\n" l) const
+noteEditor = UpdateSharedUsing id (const id) (const o Just) textArea
+listEditor = UpdateSharedAs (split "\n") (\_ l -> join "\n" l) (const o Just)
 
 toMaybe (Value v _) =  (Just v)
 toMaybe _   =  Nothing

Tests/Unit/iTasks/WF/Tasks/Core/UnitTests.icl

@@ -11,7 +11,7 @@ minimalInteractUI = skip (testTaskOutput "Initial UI of minimal interaction task
 where
 	task :: Task ((),String)
 	task = interactR unitShare handlers gEditor{|*|}
-	handlers = {onInit = \() -> ((),Update "Hello world"), onEdit = \_ l -> (l,Nothing), onRefresh = \_ l v -> (l,fromJust v,Nothing)}
+	handlers = {onInit = \() -> ((),Update "Hello world"), onEdit = \_ l -> (l,Nothing), onRefresh = \_ l v -> (l,v,Nothing)}
 
 	events = [Left ResetEvent]
 	exp = [TOUIChange (ReplaceUI expMinimalEditorUI)]

Tools/CodeQualityMonitor.icl

@@ -209,7 +209,7 @@ where
 		= Title "Edit code" @>> updateSharedInformation 
 			[UpdateSharedUsing (\{InspectState|lines} -> join OS_NEWLINE lines)
                          (\s c -> {InspectState|s & lines = split OS_NEWLINE c})
-						 const
+						 (const o Just)
                          aceTextArea] state
 
 	buildExecutable :: FilePath (Shared sds InspectState) -> Task () | RWShared sds