Do not defer property and child assignments anymore

dphfox · Apr 15, 2024 · 0550bf0 · 0550bf0
1 parent d3b43f8
commit 0550bf0
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Showing 4 changed files with 11 additions and 50 deletions.
diff --git a/docs/tutorials/roblox/hydration.md b/docs/tutorials/roblox/hydration.md
@@ -17,8 +17,8 @@ and hiding buttons.
 </figure>
 
 Fusion provides a `Hydrate` function for hydrating an instance using a table
-of properties. If you pass in Fusion objects, changes will be applied on the
-next frame:
+of properties. If you pass in Fusion objects, changes will be applied
+immediately:
 
 ```Lua
 local showUI = scope:Value(false)
@@ -73,7 +73,7 @@ local instance = scope:Hydrate(workspace.Part) {
 
 If you pass in constant values for properties, they'll be applied to the
 instance directly. However, if you pass in a Fusion object (like `Value`), then
-changes will be applied on the next frame:
+changes will be applied immediately:
 
 ```Lua
 local message = scope:Value("Loading...")

diff --git a/src/Instances/Attribute.luau b/src/Instances/Attribute.luau
@@ -10,7 +10,6 @@ local task = nil -- Disable usage of Roblox's task scheduler
 
 local Package = script.Parent.Parent
 local Types = require(Package.Types)
-local External = require(Package.External)
 local logError = require(Package.Logging.logError)
 local logWarn = require(Package.Logging.logWarn)
 local isState = require(Package.State.isState)
@@ -38,18 +37,9 @@ local function Attribute(
 				elseif whichLivesLonger(scope, applyTo, value.scope, value) == "definitely-a" then
 					logWarn("possiblyOutlives", `The {value.kind} object, bound to [Attribute "{attributeName}"],`, `the {applyTo.ClassName} instance`)
 				end
-				local didDefer = false
-				local function update()
-					if not didDefer then
-						didDefer = true
-						External.doTaskDeferred(function()
-							didDefer = false
-							applyTo:SetAttribute(attributeName, peek(value))
-						end)
-					end
-				end
-				applyTo:SetAttribute(attributeName, peek(value))
-				table.insert(scope, Observer(scope, value :: any):onChange(update))
+				Observer(scope, value :: any):onBind(function()
+					applyTo:SetAttribute(attributeName, peek(value))
+				end)
 			else
 				applyTo:SetAttribute(attributeName, value)
 			end

diff --git a/src/Instances/Children.luau b/src/Instances/Children.luau
@@ -40,18 +40,10 @@ return {
 		local newScopes: {[Types.StateObject<unknown>]: Types.Scope<unknown>} = {}
 		local oldScopes: {[Types.StateObject<unknown>]: Types.Scope<unknown>} = {}
 
-		local updateQueued = false
-		local queueUpdate: () -> ()
-
 		-- Rescans this key's value to find new instances to parent and state objects
 		-- to observe for changes; then unparents instances no longer found and
 		-- disconnects observers for state objects no longer present.
 		local function updateChildren()
-			if not updateQueued then
-				return -- this update may have been canceled by destruction, etc.
-			end
-			updateQueued = false
-
 			oldParented, newParented = newParented, oldParented
 			oldScopes, newScopes = newScopes, oldScopes
 			table.clear(newParented)
@@ -97,7 +89,7 @@ return {
 					if childScope == nil then
 						-- wasn't previously present
 						childScope = {}
-						Observer(childScope, child):onChange(queueUpdate)
+						Observer(childScope, child):onChange(updateChildren)
 					else
 						-- previously here; we want to reuse, so remove from old
 						-- set so we don't encounter it during unparenting
@@ -148,21 +140,12 @@ return {
 			end
 		end
 
-		queueUpdate = function()
-			if not updateQueued then
-				updateQueued = true
-				External.doTaskDeferred(updateChildren)
-			end
-		end
-
 		table.insert(scope, function()
 			value = nil
-			updateQueued = true
 			updateChildren()
 		end)
 
 		-- perform initial child parenting
-		updateQueued = true
 		updateChildren()
 	end
 } :: Types.SpecialKey
diff --git a/src/Instances/applyInstanceProps.luau b/src/Instances/applyInstanceProps.luau
@@ -18,7 +18,6 @@ local task = nil -- Disable usage of Roblox's task scheduler
 
 local Package = script.Parent.Parent
 local Types = require(Package.Types)
-local External = require(Package.External)
 local isState = require(Package.State.isState)
 local logError = require(Package.Logging.logError)
 local logWarn = require(Package.Logging.logWarn)
@@ -81,21 +80,10 @@ local function bindProperty(
 		elseif whichLivesLonger(scope, instance, value.scope, value) == "definitely-a" then
 			logWarn("possiblyOutlives", `The {value.kind} object, bound to {property},`, `the {instance.ClassName} instance`)
 		end
-
-		-- value is a state object - assign and observe for changes
-		local willUpdate = false
-		local function updateLater()
-			if not willUpdate then
-				willUpdate = true
-				External.doTaskDeferred(function()
-					willUpdate = false
-					setProperty(instance, property, peek(value))
-				end)
-			end
-		end
-
-		setProperty(instance, property, peek(value))
-		table.insert(scope, Observer(scope, value :: any):onChange(updateLater))
+		-- value is a state object - bind to changes
+		Observer(scope, value :: any):onBind(function()
+			setProperty(instance, property, peek(value))
+		end)
 	else
 		-- value is a constant - assign once only
 		setProperty(instance, property, value)