Added option to use a property as an observer

src/Kinetic/Property.cs

@@ -19,6 +19,9 @@ public T Get() =>
     public void Set(T value) =>
         Owner.Set(Offset, value);
 
+    public IObserver<T> Change =>
+        Owner.EnsureObservableFor<T>(Offset);
+
     public IObservable<T> Changed =>
         Owner.EnsureObservableFor<T>(Offset);
 

src/Kinetic/PropertyObservable.cs

@@ -19,7 +19,7 @@ protected PropertyObservable(ObservableObject owner, IntPtr offset, PropertyObse
 
 [DebuggerDisplay("Observers = {Subscriptions.GetObserversCountForDebugger()}")]
 [DebuggerTypeProxy(typeof(PropertyObservableDebugView<>))]
-internal sealed class PropertyObservable<T> : PropertyObservable, IObservableInternal<T>
+internal sealed class PropertyObservable<T> : PropertyObservable, IObservableInternal<T>, IObserver<T>
 {
     internal ObservableSubscriptions<T> Subscriptions;
 
@@ -44,4 +44,13 @@ public void Subscribe(ObservableSubscription<T> subscription) =>
 
     public void Unsubscribe(ObservableSubscription<T> subscription) =>
         Subscriptions.Unsubscribe(subscription);
+
+    public void OnCompleted()
+    { }
+
+    public void OnError(Exception error)
+    { }
+
+    public void OnNext(T value) =>
+        Owner.Set(Offset, value);
 }

test/Kinetic.Tests/ObservableObjectTests.cs

@@ -39,6 +39,25 @@ public void PropertySubscription()
         Assert.Equal(new[] { 0, 1, 2, 3 }, numbers);
     }
 
+    [Fact]
+    public void PropertyChange()
+    {
+        var test = new TestObject();
+        var numbers = new List<int>();
+
+        using (test.Number.Changed.Subscribe(
+            value => numbers.Add(value)))
+        {
+            test.Number.Change.OnNext(1);
+            test.Number.Change.OnNext(2);
+            test.Number.Change.OnNext(3);
+        }
+
+        test.Number.Set(4);
+
+        Assert.Equal(new[] { 0, 1, 2, 3 }, numbers);
+    }
+
     [Fact]
     public void SuppressNotifications()
     {