Refactor variables handling

introducing Variable objects, all functionality stays the same at this
time

history.txt

@@ -2262,3 +2262,7 @@ ______
 ------
 * Threads, Blocks: enable Zombiefication of JS-Functions
 * Morphic: Fix #563 (Paste into Chrome), thanks, @Muon, for the hint!
+
+140917
+------
+* Threads, Objects, Store: Refactor variables handling, introducing Variable objects, all functionality stays the same

objects.js

@@ -125,7 +125,7 @@ PrototypeHatBlockMorph*/
 
 // Global stuff ////////////////////////////////////////////////////////
 
-modules.objects = '2014-July-30';
+modules.objects = '2014-September-17';
 
 var SpriteMorph;
 var StageMorph;
@@ -6735,7 +6735,8 @@ WatcherMorph.prototype.update = function () {
     if (this.target && this.getter) {
         this.updateLabel();
         if (this.target instanceof VariableFrame) {
-            newValue = this.target.vars[this.getter];
+            newValue = this.target.vars[this.getter] ?
+                    this.target.vars[this.getter].value : undefined;
         } else {
             newValue = this.target[this.getter]();
         }
@@ -6820,7 +6821,7 @@ WatcherMorph.prototype.fixLayout = function () {
         this.sliderMorph.button.pressColor.b += 100;
         this.sliderMorph.setHeight(fontSize);
         this.sliderMorph.action = function (num) {
-            myself.target.vars[myself.getter] = Math.round(num);
+            myself.target.vars[myself.getter].value = Math.round(num);
         };
         this.add(this.sliderMorph);
     }

store.js

@@ -57,11 +57,11 @@ newCanvas, Costume, Sound, Audio, IDE_Morph, ScriptsMorph, BlockMorph,
 ArgMorph, InputSlotMorph, TemplateSlotMorph, CommandSlotMorph,
 FunctionSlotMorph, MultiArgMorph, ColorSlotMorph, nop, CommentMorph, isNil,
 localize, sizeOf, ArgLabelMorph, SVG_Costume, MorphicPreferences,
-SyntaxElementMorph*/
+SyntaxElementMorph, Variable*/
 
 // Global stuff ////////////////////////////////////////////////////////
 
-modules.store = '2014-July-29';
+modules.store = '2014-September-17';
 
 
 // XML_Serializer ///////////////////////////////////////////////////////
@@ -730,8 +730,8 @@ SnapSerializer.prototype.loadVariables = function (varFrame, element) {
             return;
         }
         value = child.children[0];
-        varFrame.vars[child.attributes.name] = value ?
-                myself.loadValue(value) : 0;
+        varFrame.vars[child.attributes.name] = new Variable(value ?
+                myself.loadValue(value) : 0);
     });
 };
 
@@ -1509,7 +1509,7 @@ Sound.prototype.toXML = function (serializer) {
 VariableFrame.prototype.toXML = function (serializer) {
     var myself = this;
     return Object.keys(this.vars).reduce(function (vars, v) {
-        var val = myself.vars[v],
+        var val = myself.vars[v].value,
             dta;
         if (val === undefined || val === null) {
             dta = serializer.format('<variable name="@"/>', v);

threads.js

@@ -83,7 +83,7 @@ ArgLabelMorph, localize, XML_Element, hex_sha512*/
 
 // Global stuff ////////////////////////////////////////////////////////
 
-modules.threads = '2014-August-13';
+modules.threads = '2014-September-17';
 
 var ThreadManager;
 var Process;
@@ -2982,6 +2982,20 @@ Context.prototype.stackSize = function () {
     return 1 + this.parentContext.stackSize();
 };
 
+// Variable /////////////////////////////////////////////////////////////////
+
+function Variable(value) {
+    this.value = value;
+}
+
+Variable.prototype.toString = function () {
+    return 'a Variable [' + this.value + ']';
+};
+
+Variable.prototype.copy = function () {
+    return new Variable(this.value);
+};
+
 // VariableFrame ///////////////////////////////////////////////////////
 
 function VariableFrame(parentFrame, owner) {
@@ -3049,7 +3063,7 @@ VariableFrame.prototype.setVar = function (name, value) {
 */
     var frame = this.find(name);
     if (frame) {
-        frame.vars[name] = value;
+        frame.vars[name].value = value;
     }
 };
 
@@ -3063,11 +3077,11 @@ VariableFrame.prototype.changeVar = function (name, delta) {
     var frame = this.find(name),
         value;
     if (frame) {
-        value = parseFloat(frame.vars[name]);
+        value = parseFloat(frame.vars[name].value);
         if (isNaN(value)) {
-            frame.vars[name] = delta;
+            frame.vars[name].value = delta;
         } else {
-            frame.vars[name] = value + parseFloat(delta);
+            frame.vars[name].value = value + parseFloat(delta);
         }
     }
 };
@@ -3077,7 +3091,7 @@ VariableFrame.prototype.getVar = function (name, upvars) {
         value,
         upvarReference;
     if (frame) {
-        value = frame.vars[name];
+        value = frame.vars[name].value;
         return (value === 0 ? 0
                 : value === false ? false
                         : value === '' ? ''
@@ -3101,7 +3115,7 @@ VariableFrame.prototype.getVar = function (name, upvars) {
 };
 
 VariableFrame.prototype.addVar = function (name, value) {
-    this.vars[name] = (value === 0 ? 0
+    this.vars[name] = new Variable(value === 0 ? 0
               : value === false ? false
                        : value === '' ? '' : value || 0);
 };
@@ -3159,23 +3173,11 @@ VariableFrame.prototype.allNames = function () {
     return answer;
 };
 
-// Variable /////////////////////////////////////////////////////////////////
-
-function Variable(value) {
-    this.value = value;
-}
-
-Variable.prototype.toString = function () {
-    return 'a Variable [' + this.value + ']';
-};
-
-Variable.prototype.copy = function () {
-    return new Variable(this.value);
-};
-
 // UpvarReference ///////////////////////////////////////////////////////////
 
 // ... quasi-inherits some features from VariableFrame
+// current variable refactoring efforts will make the upvar reference
+// mechanism obsolete
 
 function UpvarReference(parent) {
     this.vars = {}; // structure: {upvarName : [varName, varFrame]}
@@ -3207,7 +3209,7 @@ UpvarReference.prototype.find = function (name) {
 UpvarReference.prototype.getVar = function (name) {
     var varName = this.vars[name][0],
         varFrame = this.vars[name][1],
-        value = varFrame.vars[varName];
+        value = varFrame.vars[varName].value;
     return (value === 0 ? 0 : value || 0); // don't return null
 };