a few additional extensions and fixed BatchFrame

Author: Fijo

Assets/Src/Scripts/Data/Linq/DataObservable.cs

@@ -1,5 +1,6 @@
 using System.Reactive.Data.Linq.Observables;
 using System.Reactive.Linq;
+using System.Linq;
 
 namespace System.Reactive.Data.Linq {
     public static class DataObservable {
@@ -29,5 +30,28 @@ public static IObservable<Pair<T>> Pairwise<T>(this IObservable<T> source) {
                 throw new ArgumentNullException(nameof(source));
             return new Pairwise<T>(source);
         }
+
+        /// <summary>
+        /// same as Publish().RefCount()
+        /// </summary>
+        public static IObservable<T> Share<T>(this IObservable<T> source) {
+            return source.Publish().RefCount();
+        }
+
+        public static IObservable<TSource> Concat<TSource>(this IObservable<TSource> first, params IObservable<TSource>[] seconds) {
+            if (first is null)
+                throw new ArgumentNullException(nameof(first));
+            if (seconds is null)
+                throw new ArgumentNullException(nameof(seconds));
+            return Observable.Concat(new[] { first }.Concat(seconds));
+        }
+
+        public static IObservable<T> Merge<T>(this IObservable<T> first, params IObservable<T>[] seconds) {
+            if (first is null)
+                throw new ArgumentNullException(nameof(first));
+            if (seconds is null)
+                throw new ArgumentNullException(nameof(seconds));
+            return Observable.Merge(new[] { first }.Concat(seconds));
+        }
     }
 }

Assets/Src/Scripts/Unity/Linq/Observables/BatchFrame.cs

@@ -25,7 +25,7 @@ internal sealed class _ : Sink<T, IList<T>> {
             private bool _isRunning;
             private bool _isCompleted;
             private bool _isDisposed;
-            private List<T> _list;
+            private List<T> _list = new List<T>();
 
             public _(IObserver<IList<T>> observer, int frameCount, FrameCountType frameCountType) : base(observer) {
                 _frameCount = frameCount;

Assets/Src/Scripts/package.json

@@ -0,0 +1,15 @@
+{
+    "name": "com.system.reactive.unity",
+    "displayName": "Reactive Extensions Enrichment for Unity",
+    "version": "1.0.0",
+    "unity": "2021.2",
+    "description": "A minimalistic MVVM framework for the new Unity UI Toolkit build on EcsRx.",
+    "keywords": [ "rx", "system", "unity" ],
+    "category": "gui",
+    "dependencies": {},
+    "author": {
+        "name": "Jonas Fischer",
+        "email": "[email protected]",
+        "url": "https://github.com/Cosmic-Shores/System.Reactive.Unity"
+    }
+}

Assets/Src/Scripts/package.json.meta

@@ -200,6 +200,7 @@ PlayerSettings:
   - {fileID: 0}
   - {fileID: 0}
   - {fileID: 0}
+  - {fileID: 0}
   metroInputSource: 0
   wsaTransparentSwapchain: 0
   m_HolographicPauseOnTrackingLoss: 1