Moving Defer to AsyncEnumerableEx.

Ix.NET/Source/System.Interactive.Async.Tests/AsyncTests.Creation.cs

@@ -177,14 +177,14 @@ namespace Tests
         [Fact]
         public void Defer_Null()
         {
-            AssertThrows<ArgumentNullException>(() => AsyncEnumerable.Defer<int>(default(Func<IAsyncEnumerable<int>>)));
+            AssertThrows<ArgumentNullException>(() => AsyncEnumerableEx.Defer<int>(default(Func<IAsyncEnumerable<int>>)));
         }
 
         [Fact]
         public void Defer1()
         {
             var x = 0;
-            var xs = AsyncEnumerable.Defer<int>(() => new[] { x }.ToAsyncEnumerable());
+            var xs = AsyncEnumerableEx.Defer<int>(() => new[] { x }.ToAsyncEnumerable());
 
             {
                 var e = xs.GetAsyncEnumerator();

Ix.NET/Source/System.Interactive.Async/Defer.cs → Ix.NET/Source/System.Interactive.Async/System/Linq/Operators/Defer.cs

@@ -4,10 +4,11 @@
 
 using System.Collections.Generic;
 using System.Threading.Tasks;
+using static System.Linq.AsyncEnumerable;
 
 namespace System.Linq
 {
-    public static partial class AsyncEnumerable
+    public static partial class AsyncEnumerableEx
     {
         public static IAsyncEnumerable<TSource> Defer<TSource>(Func<IAsyncEnumerable<TSource>> factory)
         {