work in progress: observable implementation using detailed change records

lib/templating.dart

Index: lib/templating.dart
diff --git a/lib/templating.dart b/lib/templating.dart
index 3f5693f2400065572969f2908a98d9f399120990..3063211294301461b72ccef7e1aae733a13135f0 100644
--- a/lib/templating.dart
+++ b/lib/templating.dart
@@ -10,6 +10,8 @@ import 'dart:html';
 import 'dart:uri';
 import 'package:web_ui/safe_html.dart';
 import 'package:web_ui/watcher.dart';
+import 'package:web_ui/observe.dart';
+export 'src/utils.dart' show setImmediate;
 
 /**
  * Take the value of a bound expression and creates an HTML node with its value.
@@ -136,7 +138,7 @@ void updateCssClass(Element elem, bool addClasses, classes) {
  *         bindCssClasses(e, () => class1);
  *         bindCssClasses(e, () => class2);
  */
-WatcherDisposer bindCssClasses(Element elem, dynamic exp()) {
+ChangeUnobserver bindCssClasses(Element elem, dynamic exp()) {
   return watchAndInvoke(exp, (e) {
     updateCssClass(elem, false, e.oldValue);
     updateCssClass(elem, true, e.newValue);
@@ -144,7 +146,7 @@ WatcherDisposer bindCssClasses(Element elem, dynamic exp()) {
 }
 
 /** Bind the result of [exp] to the style attribute in [elem]. */
-WatcherDisposer bindStyle(Element elem, Map<String, String> exp()) {
+ChangeUnobserver bindStyle(Element elem, Map<String, String> exp()) {
   return watchAndInvoke(exp, (e) {
     if (e.oldValue is Map<String, String>) {
       var props = e.newValue;
@@ -237,8 +239,8 @@ class Listener extends TemplateItem {
 /** Represents a generic data binding and a corresponding action. */
 class Binding extends TemplateItem {
   final exp;
-  final ValueWatcher action;
-  WatcherDisposer stopper;
+  final ChangeObserver action;
+  ChangeUnobserver stopper;
 
   Binding(this.exp, this.action);
 
@@ -257,7 +259,7 @@ class Binding extends TemplateItem {
 class StyleAttrBinding extends TemplateItem {
   final exp;
   final Element elem;
-  WatcherDisposer stopper;
+  ChangeUnobserver stopper;
 
   StyleAttrBinding(this.elem, this.exp);
 
@@ -276,7 +278,7 @@ class StyleAttrBinding extends TemplateItem {
 class ClassAttrBinding extends TemplateItem {
   final Element elem;
   final exp;
-  WatcherDisposer stopper;
+  ChangeUnobserver stopper;
 
   ClassAttrBinding(this.elem, this.exp);
 
@@ -311,7 +313,7 @@ class DomPropertyBinding extends TemplateItem {
    */
   final bool isUrl;
 
-  WatcherDisposer stopper;
+  ChangeUnobserver stopper;
 
   DomPropertyBinding(this.getter, this.setter, this.isUrl);
 
@@ -375,7 +377,7 @@ class Template extends TemplateItem {
   }
 
   /** Run [action] when [exp] changes (while this template is visible).  */
-  void bind(exp, ValueWatcher action) {
+  void bind(exp, ChangeObserver action) {
     children.add(new Binding(exp, action));
   }
 
@@ -488,7 +490,7 @@ abstract class PlaceholderTemplate extends Template {
   /** Expression watch by this template (condition or loop expression). */
   final exp;
 
-  WatcherDisposer stopper;
+  ChangeUnobserver stopper;
 
   PlaceholderTemplate(Node reference, this.exp)
       : super(reference);
@@ -589,7 +591,7 @@ class LoopTemplate extends PlaceholderTemplate {
 class LoopTemplateInAttribute extends Template {
   final LoopIterationSetup iterSetup;
   final exp;
-  WatcherDisposer stopper;
+  ChangeUnobserver stopper;
 
   LoopTemplateInAttribute(Node node, this.exp, this.iterSetup) : super(node);