Better nullable coverage.

Author: Oren (electricessence)

Open.ChannelExtensions/Extensions.Filter.cs

@@ -29,7 +29,9 @@ public override bool TryRead(out T item)
 						return true;
 				}
 
+#pragma warning disable CS8653 // A default expression introduces a null value for a type parameter.
 				item = default;
+#pragma warning restore CS8653 // A default expression introduces a null value for a type parameter.
 				return false;
 			}
 

Open.ChannelExtensions/Extensions._.cs

@@ -71,7 +71,7 @@ public static ValueTask WaitToWriteAndThrowIfClosedAsync<T>(this ChannelWriter<T
 		/// <typeparam name="TRead">The type being read from the reader.</typeparam>
 		/// <typeparam name="Exception">The optional exception to include with completion.</typeparam>
 		/// <returns>The reader's completion task.</returns>
-		public static Task CompleteAsync<TWrite, TRead>(this Channel<TWrite, TRead> channel, Exception exception = null)
+		public static Task CompleteAsync<TWrite, TRead>(this Channel<TWrite, TRead> channel, Exception? exception = null)
 		{
 			channel.Writer.Complete(exception);
 			return channel.Reader.Completion;