简化ETTask

Server/Model/Server.Model.csproj

@@ -20,18 +20,9 @@
   </PropertyGroup>
   <ItemGroup>
     <Compile Remove="Libs\**" />
-    <Compile Include="..\..\Unity\Assets\Model\Base\Async\AsyncUnit.cs">
-      <Link>Base\Async\AsyncUnit.cs</Link>
-    </Compile>
-    <Compile Include="..\..\Unity\Assets\Model\Base\Async\CancellationTokenExtensions.cs">
-      <Link>Base\Async\CancellationTokenExtensions.cs</Link>
-    </Compile>
     <Compile Include="..\..\Unity\Assets\Model\Base\Async\ETAsyncTaskMethodBuilder.cs">
       <Link>Base\Async\ETAsyncTaskMethodBuilder.cs</Link>
     </Compile>
-    <Compile Include="..\..\Unity\Assets\Model\Base\Async\ETAsyncTaskVoidMethodBuilder.cs">
-      <Link>Base\Async\ETAsyncTaskVoidMethodBuilder.cs</Link>
-    </Compile>
     <Compile Include="..\..\Unity\Assets\Model\Base\Async\ETTask.cs">
       <Link>Base\Async\ETTask.cs</Link>
     </Compile>
@@ -41,15 +32,9 @@
     <Compile Include="..\..\Unity\Assets\Model\Base\Async\ETTaskFactory.cs">
       <Link>Base\Async\ETTaskFactory.cs</Link>
     </Compile>
-    <Compile Include="..\..\Unity\Assets\Model\Base\Async\ETTaskVoid.cs">
-      <Link>Base\Async\ETTaskVoid.cs</Link>
-    </Compile>
     <Compile Include="..\..\Unity\Assets\Model\Base\Async\IAwaiter.cs">
       <Link>Base\Async\IAwaiter.cs</Link>
     </Compile>
-    <Compile Include="..\..\Unity\Assets\Model\Base\Async\LazyPromise.cs">
-      <Link>Base\Async\LazyPromise.cs</Link>
-    </Compile>
     <Compile Include="..\..\Unity\Assets\Model\Base\Async\MoveNextRunner.cs">
       <Link>Base\Async\MoveNextRunner.cs</Link>
     </Compile>

Unity/Assets/Model/Base/Async/AsyncUnit.cs

@@ -1,24 +0,0 @@
-using System;
-
-namespace ETModel
-{
-    public struct AsyncUnit: IEquatable<AsyncUnit>
-    {
-        public static readonly AsyncUnit Default = new AsyncUnit();
-
-        public override int GetHashCode()
-        {
-            return 0;
-        }
-
-        public bool Equals(AsyncUnit other)
-        {
-            return true;
-        }
-
-        public override string ToString()
-        {
-            return "()";
-        }
-    }
-}

Unity/Assets/Model/Base/Async/AsyncUnit.cs.meta

@@ -1,11 +0,0 @@
-fileFormatVersion: 2
-guid: 2826256cdc0af9e4b832ff24d04b58da
-MonoImporter:
-  externalObjects: {}
-  serializedVersion: 2
-  defaultReferences: []
-  executionOrder: 0
-  icon: {instanceID: 0}
-  userData: 
-  assetBundleName: 
-  assetBundleVariant: 

Unity/Assets/Model/Base/Async/CancellationTokenExtensions.cs

@@ -1,72 +0,0 @@
-using System;
-using System.Threading;
-
-namespace ETModel
-{
-    public static class CancellationTokenExtensions
-    {
-        private static readonly Action<object> cancellationTokenCallback = Callback;
-
-        public static (ETTask, CancellationTokenRegistration) ToETTask(this CancellationToken cts)
-        {
-            if (cts.IsCancellationRequested)
-            {
-                return (ETTask.FromCanceled(cts), default);
-            }
-
-            var promise = new ETTaskCompletionSource<AsyncUnit>();
-            return (promise.Task, cts.RegisterWithoutCaptureExecutionContext(cancellationTokenCallback, promise));
-        }
-
-        private static void Callback(object state)
-        {
-            var promise = (ETTaskCompletionSource<AsyncUnit>) state;
-            promise.TrySetResult(AsyncUnit.Default);
-        }
-
-        public static CancellationTokenRegistration RegisterWithoutCaptureExecutionContext(this CancellationToken cancellationToken, Action callback)
-        {
-            bool restoreFlow = false;
-            if (!ExecutionContext.IsFlowSuppressed())
-            {
-                ExecutionContext.SuppressFlow();
-                restoreFlow = true;
-            }
-
-            try
-            {
-                return cancellationToken.Register(callback, false);
-            }
-            finally
-            {
-                if (restoreFlow)
-                {
-                    ExecutionContext.RestoreFlow();
-                }
-            }
-        }
-
-        public static CancellationTokenRegistration RegisterWithoutCaptureExecutionContext(this CancellationToken cancellationToken,
-        Action<object> callback, object state)
-        {
-            bool restoreFlow = false;
-            if (!ExecutionContext.IsFlowSuppressed())
-            {
-                ExecutionContext.SuppressFlow();
-                restoreFlow = true;
-            }
-
-            try
-            {
-                return cancellationToken.Register(callback, state, false);
-            }
-            finally
-            {
-                if (restoreFlow)
-                {
-                    ExecutionContext.RestoreFlow();
-                }
-            }
-        }
-    }
-}

Unity/Assets/Model/Base/Async/CancellationTokenExtensions.cs.meta

@@ -1,11 +0,0 @@
-fileFormatVersion: 2
-guid: 1ede9bbc65a28b646b1d1313258bb658
-MonoImporter:
-  externalObjects: {}
-  serializedVersion: 2
-  defaultReferences: []
-  executionOrder: 0
-  icon: {instanceID: 0}
-  userData: 
-  assetBundleName: 
-  assetBundleVariant: 

Unity/Assets/Model/Base/Async/ETAsyncTaskMethodBuilder.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Diagnostics;
 using System.Runtime.CompilerServices;
 using System.Security;
 
@@ -7,7 +6,7 @@ namespace ETModel
 {
     public struct ETAsyncTaskMethodBuilder
     {
-        private ETTaskCompletionSource promise;
+        private ETTaskCompletionSource tcs;
         private Action moveNext;
 
         // 1. Static Create method.
@@ -24,9 +23,9 @@ namespace ETModel
         {
             get
             {
-                if (promise != null)
+                if (this.tcs != null)
                 {
-                    return promise.Task;
+                    return this.tcs.Task;
                 }
 
                 if (moveNext == null)
@@ -34,8 +33,8 @@ namespace ETModel
                     return ETTask.CompletedTask;
                 }
 
-                this.promise = new ETTaskCompletionSource();
-                return this.promise.Task;
+                this.tcs = new ETTaskCompletionSource();
+                return this.tcs.Task;
             }
         }
 
@@ -43,18 +42,18 @@ namespace ETModel
         //[DebuggerHidden]
         public void SetException(Exception exception)
         {
-            if (promise == null)
+            if (this.tcs == null)
             {
-                promise = new ETTaskCompletionSource();
+                this.tcs = new ETTaskCompletionSource();
             }
 
             if (exception is OperationCanceledException ex)
             {
-                promise.TrySetCanceled(ex);
+                this.tcs.TrySetCanceled(ex);
             }
             else
             {
-                promise.TrySetException(exception);
+                this.tcs.TrySetException(exception);
             }
         }
 
@@ -67,12 +66,12 @@ namespace ETModel
             }
             else
             {
-                if (promise == null)
+                if (this.tcs == null)
                 {
-                    promise = new ETTaskCompletionSource();
+                    this.tcs = new ETTaskCompletionSource();
                 }
 
-                promise.TrySetResult();
+                this.tcs.TrySetResult();
             }
         }
 
@@ -84,9 +83,9 @@ namespace ETModel
         {
             if (moveNext == null)
             {
-                if (promise == null)
+                if (this.tcs == null)
                 {
-                    promise = new ETTaskCompletionSource(); // built future.
+                    this.tcs = new ETTaskCompletionSource(); // built future.
                 }
 
                 var runner = new MoveNextRunner<TStateMachine>();
@@ -106,9 +105,9 @@ namespace ETModel
         {
             if (moveNext == null)
             {
-                if (promise == null)
+                if (this.tcs == null)
                 {
-                    promise = new ETTaskCompletionSource(); // built future.
+                    this.tcs = new ETTaskCompletionSource(); // built future.
                 }
 
                 var runner = new MoveNextRunner<TStateMachine>();
@@ -121,8 +120,7 @@ namespace ETModel
 
         // 7. Start
         //[DebuggerHidden]
-        public void Start<TStateMachine>(ref TStateMachine stateMachine)
-                where TStateMachine : IAsyncStateMachine
+        public void Start<TStateMachine>(ref TStateMachine stateMachine) where TStateMachine : IAsyncStateMachine
         {
             stateMachine.MoveNext();
         }
@@ -137,7 +135,7 @@ namespace ETModel
     public struct ETAsyncTaskMethodBuilder<T>
     {
         private T result;
-        private ETTaskCompletionSource<T> promise;
+        private ETTaskCompletionSource<T> tcs;
         private Action moveNext;
 
         // 1. Static Create method.
@@ -154,9 +152,9 @@ namespace ETModel
         {
             get
             {
-                if (promise != null)
+                if (this.tcs != null)
                 {
-                    return new ETTask<T>(promise);
+                    return new ETTask<T>(this.tcs);
                 }
 
                 if (moveNext == null)
@@ -164,8 +162,8 @@ namespace ETModel
                     return new ETTask<T>(result);
                 }
 
-                this.promise = new ETTaskCompletionSource<T>();
-                return new ETTask<T>(this.promise);
+                this.tcs = new ETTaskCompletionSource<T>();
+                return this.tcs.Task;
             }
         }
 
@@ -173,37 +171,37 @@ namespace ETModel
         //[DebuggerHidden]
         public void SetException(Exception exception)
         {
-            if (promise == null)
+            if (this.tcs == null)
             {
-                promise = new ETTaskCompletionSource<T>();
+                this.tcs = new ETTaskCompletionSource<T>();
             }
 
             if (exception is OperationCanceledException ex)
             {
-                promise.TrySetCanceled(ex);
+                this.tcs.TrySetCanceled(ex);
             }
             else
             {
-                promise.TrySetException(exception);
+                this.tcs.TrySetException(exception);
             }
         }
 
         // 4. SetResult
         //[DebuggerHidden]
-        public void SetResult(T result)
+        public void SetResult(T ret)
         {
             if (moveNext == null)
             {
-                this.result = result;
+                this.result = ret;
             }
             else
             {
-                if (promise == null)
+                if (this.tcs == null)
                 {
-                    promise = new ETTaskCompletionSource<T>();
+                    this.tcs = new ETTaskCompletionSource<T>();
                 }
 
-                promise.TrySetResult(result);
+                this.tcs.TrySetResult(ret);
             }
         }
 
@@ -215,9 +213,9 @@ namespace ETModel
         {
             if (moveNext == null)
             {
-                if (promise == null)
+                if (this.tcs == null)
                 {
-                    promise = new ETTaskCompletionSource<T>(); // built future.
+                    this.tcs = new ETTaskCompletionSource<T>(); // built future.
                 }
 
                 var runner = new MoveNextRunner<TStateMachine>();
@@ -237,9 +235,9 @@ namespace ETModel
         {
             if (moveNext == null)
             {
-                if (promise == null)
+                if (this.tcs == null)
                 {
-                    promise = new ETTaskCompletionSource<T>(); // built future.
+                    this.tcs = new ETTaskCompletionSource<T>(); // built future.
                 }
 
                 var runner = new MoveNextRunner<TStateMachine>();
@@ -252,8 +250,7 @@ namespace ETModel
 
         // 7. Start
         //[DebuggerHidden]
-        public void Start<TStateMachine>(ref TStateMachine stateMachine)
-                where TStateMachine : IAsyncStateMachine
+        public void Start<TStateMachine>(ref TStateMachine stateMachine) where TStateMachine : IAsyncStateMachine
         {
             stateMachine.MoveNext();
         }

Unity/Assets/Model/Base/Async/ETAsyncTaskVoidMethodBuilder.cs

@@ -1,82 +0,0 @@
-using System;
-using System.Runtime.CompilerServices;
-using System.Security;
-
-namespace ETModel
-{
-    public struct ETAsyncTaskVoidMethodBuilder
-    {
-        private Action moveNext;
-
-        // 1. Static Create method.
-        //[DebuggerHidden]
-        public static ETAsyncTaskVoidMethodBuilder Create()
-        {
-            ETAsyncTaskVoidMethodBuilder builder = new ETAsyncTaskVoidMethodBuilder();
-            return builder;
-        }
-
-        // 2. TaskLike Task property(void)
-        public ETTaskVoid Task => default;
-
-        // 3. SetException
-        //[DebuggerHidden]
-        public void SetException(Exception exception)
-        {
-        }
-
-        // 4. SetResult
-        //[DebuggerHidden]
-        public void SetResult()
-        {
-            // do nothing
-        }
-
-        // 5. AwaitOnCompleted
-        //[DebuggerHidden]
-        public void AwaitOnCompleted<TAwaiter, TStateMachine>(ref TAwaiter awaiter, ref TStateMachine stateMachine)
-                where TAwaiter : INotifyCompletion
-                where TStateMachine : IAsyncStateMachine
-        {
-            if (moveNext == null)
-            {
-                var runner = new MoveNextRunner<TStateMachine>();
-                moveNext = runner.Run;
-                runner.StateMachine = stateMachine; // set after create delegate.
-            }
-
-            awaiter.OnCompleted(moveNext);
-        }
-
-        // 6. AwaitUnsafeOnCompleted
-        //[DebuggerHidden]
-        [SecuritySafeCritical]
-        public void AwaitUnsafeOnCompleted<TAwaiter, TStateMachine>(ref TAwaiter awaiter, ref TStateMachine stateMachine)
-                where TAwaiter : ICriticalNotifyCompletion
-                where TStateMachine : IAsyncStateMachine
-        {
-            if (moveNext == null)
-            {
-                var runner = new MoveNextRunner<TStateMachine>();
-                moveNext = runner.Run;
-                runner.StateMachine = stateMachine; // set after create delegate.
-            }
-
-            awaiter.UnsafeOnCompleted(moveNext);
-        }
-
-        // 7. Start
-        //[DebuggerHidden]
-        public void Start<TStateMachine>(ref TStateMachine stateMachine)
-                where TStateMachine : IAsyncStateMachine
-        {
-            stateMachine.MoveNext();
-        }
-
-        // 8. SetStateMachine
-        //[DebuggerHidden]
-        public void SetStateMachine(IAsyncStateMachine stateMachine)
-        {
-        }
-    }
-}

Unity/Assets/Model/Base/Async/ETAsyncTaskVoidMethodBuilder.cs.meta

@@ -1,11 +0,0 @@
-fileFormatVersion: 2
-guid: 390ef7e019b703f46900fcc7dde998f1
-MonoImporter:
-  externalObjects: {}
-  serializedVersion: 2
-  defaultReferences: []
-  executionOrder: 0
-  icon: {instanceID: 0}
-  userData: 
-  assetBundleName: 
-  assetBundleVariant: 

Unity/Assets/Model/Base/Async/ETTask.cs

@@ -10,8 +10,6 @@ namespace ETModel
     [AsyncMethodBuilder(typeof (ETAsyncTaskMethodBuilder))]
     public partial struct ETTask: IEquatable<ETTask>
     {
-        private static readonly ETTask<AsyncUnit> DefaultAsyncUnitTask = new ETTask<AsyncUnit>(AsyncUnit.Default);
-
         private readonly IAwaiter awaiter;
 
         //[DebuggerHidden]
@@ -20,12 +18,6 @@ namespace ETModel
             this.awaiter = awaiter;
         }
 
-        //[DebuggerHidden]
-        public ETTask(Func<ETTask> factory)
-        {
-            this.awaiter = new LazyPromise(factory);
-        }
-
         //[DebuggerHidden]
         public AwaiterStatus Status => awaiter?.Status ?? AwaiterStatus.Succeeded;
 
@@ -47,23 +39,6 @@ namespace ETModel
             return new Awaiter(this);
         }
 
-        /// <summary>
-        /// returns (bool IsCanceled) instead of throws OperationCanceledException.
-        /// </summary>
-        public ETTask<bool> SuppressCancellationThrow()
-        {
-            AwaiterStatus status = Status;
-            switch (status)
-            {
-                case AwaiterStatus.Succeeded:
-                    return CompletedTasks.False;
-                case AwaiterStatus.Canceled:
-                    return CompletedTasks.True;
-                default:
-                    return new ETTask<bool>(new IsCanceledAwaiter(this.awaiter));
-            }
-        }
-
         public bool Equals(ETTask other)
         {
             if (this.awaiter == null && other.awaiter == null)
@@ -96,58 +71,6 @@ namespace ETModel
                     : "(" + this.awaiter.Status + ")";
         }
 
-        public static implicit operator ETTask<AsyncUnit>(ETTask task)
-        {
-            if (task.awaiter == null)
-            {
-                return DefaultAsyncUnitTask;
-            }
-
-            if (task.awaiter.IsCompleted)
-            {
-                return DefaultAsyncUnitTask;
-            }
-
-            // UniTask<T> -> UniTask is free but UniTask -> UniTask<T> requires wrapping cost.
-            return new ETTask<AsyncUnit>(new AsyncUnitAwaiter(task.awaiter));
-
-        }
-
-        private class AsyncUnitAwaiter: IAwaiter<AsyncUnit>
-        {
-            private readonly IAwaiter awaiter;
-
-            public AsyncUnitAwaiter(IAwaiter awaiter)
-            {
-                this.awaiter = awaiter;
-            }
-
-            public bool IsCompleted => awaiter.IsCompleted;
-
-            public AwaiterStatus Status => awaiter.Status;
-
-            public AsyncUnit GetResult()
-            {
-                awaiter.GetResult();
-                return AsyncUnit.Default;
-            }
-
-            public void OnCompleted(Action continuation)
-            {
-                awaiter.OnCompleted(continuation);
-            }
-
-            public void UnsafeOnCompleted(Action continuation)
-            {
-                awaiter.UnsafeOnCompleted(continuation);
-            }
-
-            void IAwaiter.GetResult()
-            {
-                awaiter.GetResult();
-            }
-        }
-
         private class IsCanceledAwaiter: IAwaiter<bool>
         {
             private readonly IAwaiter awaiter;
@@ -261,13 +184,6 @@ namespace ETModel
             this.awaiter = awaiter;
         }
 
-        //[DebuggerHidden]
-        public ETTask(Func<ETTask<T>> factory)
-        {
-            this.result = default;
-            this.awaiter = new LazyPromise<T>(factory);
-        }
-
         //[DebuggerHidden]
         public AwaiterStatus Status => awaiter?.Status ?? AwaiterStatus.Succeeded;
 
@@ -294,25 +210,6 @@ namespace ETModel
             return new Awaiter(this);
         }
 
-        /// <summary>
-        /// returns (bool IsCanceled, T Result) instead of throws OperationCanceledException.
-        /// </summary>
-        public ETTask<(bool IsCanceled, T Result)> SuppressCancellationThrow()
-        {
-            var status = Status;
-            if (status == AwaiterStatus.Succeeded)
-            {
-                return new ETTask<(bool, T)>((false, Result));
-            }
-
-            if (status == AwaiterStatus.Canceled)
-            {
-                return new ETTask<(bool, T)>((true, default));
-            }
-
-            return new ETTask<(bool, T)>(new IsCanceledAwaiter(awaiter));
-        }
-
         public bool Equals(ETTask<T> other)
         {
             if (this.awaiter == null && other.awaiter == null)
@@ -360,45 +257,6 @@ namespace ETModel
             return new ETTask();
         }
 
-        private class IsCanceledAwaiter: IAwaiter<(bool, T)>
-        {
-            private readonly IAwaiter<T> awaiter;
-
-            public IsCanceledAwaiter(IAwaiter<T> awaiter)
-            {
-                this.awaiter = awaiter;
-            }
-
-            public bool IsCompleted => awaiter.IsCompleted;
-
-            public AwaiterStatus Status => awaiter.Status;
-
-            public (bool, T) GetResult()
-            {
-                if (awaiter.Status == AwaiterStatus.Canceled)
-                {
-                    return (true, default);
-                }
-
-                return (false, awaiter.GetResult());
-            }
-
-            public void OnCompleted(Action continuation)
-            {
-                awaiter.OnCompleted(continuation);
-            }
-
-            public void UnsafeOnCompleted(Action continuation)
-            {
-                awaiter.UnsafeOnCompleted(continuation);
-            }
-
-            void IAwaiter.GetResult()
-            {
-                awaiter.GetResult();
-            }
-        }
-
         public struct Awaiter: IAwaiter<T>
         {
             private readonly ETTask<T> task;

Unity/Assets/Model/Base/Async/ETTaskCompletionSource.cs

@@ -4,30 +4,6 @@ using System.Runtime.ExceptionServices;
 
 namespace ETModel
 {
-    internal class ExceptionHolder
-    {
-        private readonly ExceptionDispatchInfo exception;
-        private bool calledGet;
-
-        public ExceptionHolder(ExceptionDispatchInfo exception)
-        {
-            this.exception = exception;
-        }
-
-        public ExceptionDispatchInfo GetException()
-        {
-            if (calledGet)
-            {
-                return this.exception;
-            }
-
-            this.calledGet = true;
-            GC.SuppressFinalize(this);
-
-            return exception;
-        }
-    }
-
     public class ETTaskCompletionSource: IAwaiter
     {
         // State(= AwaiterStatus)
@@ -37,7 +13,7 @@ namespace ETModel
         private const int Canceled = 3;
 
         private int state;
-        private ExceptionHolder exception;
+        private ExceptionDispatchInfo exception;
         private Action continuation; // action or list
 
         AwaiterStatus IAwaiter.Status => (AwaiterStatus) state;
@@ -53,15 +29,13 @@ namespace ETModel
                 case Succeeded:
                     return;
                 case Faulted:
-                    this.exception.GetException().Throw();
+                    this.exception?.Throw();
+                    this.exception = null;
                     return;
                 case Canceled:
                 {
-                    if (this.exception != null)
-                    {
-                        this.exception.GetException().Throw(); // guranteed operation canceled exception.
-                    }
-
+                    this.exception?.Throw(); // guranteed operation canceled exception.
+                    this.exception = null;
                     throw new OperationCanceledException();
                 }
                 default:
@@ -127,7 +101,7 @@ namespace ETModel
 
             this.state = Faulted;
 
-            this.exception = new ExceptionHolder(ExceptionDispatchInfo.Capture(e));
+            this.exception = ExceptionDispatchInfo.Capture(e);
             this.TryInvokeContinuation();
             return true;
 
@@ -156,7 +130,7 @@ namespace ETModel
 
             this.state = Canceled;
 
-            this.exception = new ExceptionHolder(ExceptionDispatchInfo.Capture(e));
+            this.exception = ExceptionDispatchInfo.Capture(e);
             this.TryInvokeContinuation();
             return true;
 
@@ -178,13 +152,12 @@ namespace ETModel
 
         private int state;
         private T value;
-        private ExceptionHolder exception;
+        private ExceptionDispatchInfo exception;
         private Action continuation; // action or list
 
         bool IAwaiter.IsCompleted => state != Pending;
 
         public ETTask<T> Task => new ETTask<T>(this);
-        public ETTask UnitTask => new ETTask(this);
 
         AwaiterStatus IAwaiter.Status => (AwaiterStatus) state;
 
@@ -195,15 +168,13 @@ namespace ETModel
                 case Succeeded:
                     return this.value;
                 case Faulted:
-                    this.exception.GetException().Throw();
+                    this.exception?.Throw();
+                    this.exception = null;
                     return default;
                 case Canceled:
                 {
-                    if (this.exception != null)
-                    {
-                        this.exception.GetException().Throw(); // guranteed operation canceled exception.
-                    }
-
+                    this.exception?.Throw(); // guranteed operation canceled exception.
+                    this.exception = null;
                     throw new OperationCanceledException();
                 }
                 default:
@@ -270,7 +241,7 @@ namespace ETModel
 
             this.state = Faulted;
 
-            this.exception = new ExceptionHolder(ExceptionDispatchInfo.Capture(e));
+            this.exception = ExceptionDispatchInfo.Capture(e);
             this.TryInvokeContinuation();
             return true;
 
@@ -299,7 +270,7 @@ namespace ETModel
 
             this.state = Canceled;
 
-            this.exception = new ExceptionHolder(ExceptionDispatchInfo.Capture(e));
+            this.exception = ExceptionDispatchInfo.Capture(e);
             this.TryInvokeContinuation();
             return true;
 

Unity/Assets/Model/Base/Async/ETTaskFactory.cs

@@ -5,27 +5,20 @@ namespace ETModel
 {
     public partial struct ETTask
     {
-        private static readonly ETTask CanceledTask = new Func<ETTask>(() =>
-        {
-            var promise = new ETTaskCompletionSource<AsyncUnit>();
-            promise.TrySetCanceled();
-            return new ETTask(promise);
-        })();
-
         public static ETTask CompletedTask => new ETTask();
 
         public static ETTask FromException(Exception ex)
         {
-            var promise = new ETTaskCompletionSource<AsyncUnit>();
-            promise.TrySetException(ex);
-            return new ETTask(promise);
+            ETTaskCompletionSource tcs = new ETTaskCompletionSource();
+            tcs.TrySetException(ex);
+            return tcs.Task;
         }
 
         public static ETTask<T> FromException<T>(Exception ex)
         {
-            var promise = new ETTaskCompletionSource<T>();
-            promise.TrySetException(ex);
-            return new ETTask<T>(promise);
+            var tcs = new ETTaskCompletionSource<T>();
+            tcs.TrySetException(ex);
+            return tcs.Task;
         }
 
         public static ETTask<T> FromResult<T>(T value)
@@ -35,7 +28,7 @@ namespace ETModel
 
         public static ETTask FromCanceled()
         {
-            return CanceledTask;
+            return CanceledETTaskCache.Task;
         }
 
         public static ETTask<T> FromCanceled<T>()
@@ -45,22 +38,28 @@ namespace ETModel
 
         public static ETTask FromCanceled(CancellationToken token)
         {
-            var promise = new ETTaskCompletionSource<AsyncUnit>();
-            promise.TrySetException(new OperationCanceledException(token));
-            return new ETTask(promise);
+            ETTaskCompletionSource tcs = new ETTaskCompletionSource();
+            tcs.TrySetException(new OperationCanceledException(token));
+            return tcs.Task;
         }
 
         public static ETTask<T> FromCanceled<T>(CancellationToken token)
         {
-            var promise = new ETTaskCompletionSource<T>();
-            promise.TrySetException(new OperationCanceledException(token));
-            return new ETTask<T>(promise);
+            var tcs = new ETTaskCompletionSource<T>();
+            tcs.TrySetException(new OperationCanceledException(token));
+            return tcs.Task;
         }
-
-        /// <summary>shorthand of new UniTask[T](Func[UniTask[T]] factory)</summary>
-        public static ETTask<T> Lazy<T>(Func<ETTask<T>> factory)
+        
+        private static class CanceledETTaskCache
         {
-            return new ETTask<T>(factory);
+            public static readonly ETTask Task;
+
+            static CanceledETTaskCache()
+            {
+                ETTaskCompletionSource tcs = new ETTaskCompletionSource();
+                tcs.TrySetCanceled();
+                Task = tcs.Task;
+            }
         }
 
         private static class CanceledETTaskCache<T>
@@ -69,9 +68,9 @@ namespace ETModel
 
             static CanceledETTaskCache()
             {
-                var promise = new ETTaskCompletionSource<T>();
-                promise.TrySetCanceled();
-                Task = new ETTask<T>(promise);
+                var taskCompletionSource = new ETTaskCompletionSource<T>();
+                taskCompletionSource.TrySetCanceled();
+                Task = taskCompletionSource.Task;
             }
         }
     }

Unity/Assets/Model/Base/Async/ETTaskVoid.cs

@@ -1,41 +0,0 @@
-using System;
-using System.Runtime.CompilerServices;
-
-namespace ETModel
-{
-    [AsyncMethodBuilder(typeof (ETAsyncTaskVoidMethodBuilder))]
-    public struct ETTaskVoid
-    {
-        public void Forget()
-        {
-        }
-
-        //[DebuggerHidden]
-        public Awaiter GetAwaiter()
-        {
-            return new Awaiter();
-        }
-
-        public struct Awaiter: ICriticalNotifyCompletion
-        {
-            //[DebuggerHidden]
-            public bool IsCompleted => true;
-
-            //[DebuggerHidden]
-            public void GetResult()
-            {
-                throw new Exception("ETTask can't await, always fire-and-forget. use Forget instead of await.");
-            }
-
-            //[DebuggerHidden]
-            public void OnCompleted(Action continuation)
-            {
-            }
-
-            //[DebuggerHidden]
-            public void UnsafeOnCompleted(Action continuation)
-            {
-            }
-        }
-    }
-}

Unity/Assets/Model/Base/Async/ETTaskVoid.cs.meta

@@ -1,11 +0,0 @@
-fileFormatVersion: 2
-guid: 9157caacd834b5848b11553a6ea73494
-MonoImporter:
-  externalObjects: {}
-  serializedVersion: 2
-  defaultReferences: []
-  executionOrder: 0
-  icon: {instanceID: 0}
-  userData: 
-  assetBundleName: 
-  assetBundleVariant: 

Unity/Assets/Model/Base/Async/LazyPromise.cs

@@ -1,125 +0,0 @@
-using System;
-using System.Threading;
-
-namespace ETModel
-{
-    internal sealed class LazyPromise: IAwaiter
-    {
-        private Func<ETTask> factory;
-        private ETTask value;
-
-        public LazyPromise(Func<ETTask> factory)
-        {
-            this.factory = factory;
-        }
-
-        private void Create()
-        {
-            var f = Interlocked.Exchange(ref factory, null);
-            if (f != null)
-            {
-                value = f();
-            }
-        }
-
-        public bool IsCompleted
-        {
-            get
-            {
-                Create();
-                return value.IsCompleted;
-            }
-        }
-
-        public AwaiterStatus Status
-        {
-            get
-            {
-                Create();
-                return value.Status;
-            }
-        }
-
-        public void GetResult()
-        {
-            Create();
-            value.GetResult();
-        }
-
-        void IAwaiter.GetResult()
-        {
-            GetResult();
-        }
-
-        public void UnsafeOnCompleted(Action continuation)
-        {
-            Create();
-            value.GetAwaiter().UnsafeOnCompleted(continuation);
-        }
-
-        public void OnCompleted(Action continuation)
-        {
-            UnsafeOnCompleted(continuation);
-        }
-    }
-
-    internal sealed class LazyPromise<T>: IAwaiter<T>
-    {
-        private Func<ETTask<T>> factory;
-        private ETTask<T> value;
-
-        public LazyPromise(Func<ETTask<T>> factory)
-        {
-            this.factory = factory;
-        }
-
-        private void Create()
-        {
-            var f = Interlocked.Exchange(ref factory, null);
-            if (f != null)
-            {
-                value = f();
-            }
-        }
-
-        public bool IsCompleted
-        {
-            get
-            {
-                Create();
-                return value.IsCompleted;
-            }
-        }
-
-        public AwaiterStatus Status
-        {
-            get
-            {
-                Create();
-                return value.Status;
-            }
-        }
-
-        public T GetResult()
-        {
-            Create();
-            return value.Result;
-        }
-
-        void IAwaiter.GetResult()
-        {
-            GetResult();
-        }
-
-        public void UnsafeOnCompleted(Action continuation)
-        {
-            Create();
-            value.GetAwaiter().UnsafeOnCompleted(continuation);
-        }
-
-        public void OnCompleted(Action continuation)
-        {
-            UnsafeOnCompleted(continuation);
-        }
-    }
-}

Unity/Assets/Model/Base/Async/LazyPromise.cs.meta

@@ -1,11 +0,0 @@
-fileFormatVersion: 2
-guid: bf276347e994763428d1a563259218f5
-MonoImporter:
-  externalObjects: {}
-  serializedVersion: 2
-  defaultReferences: []
-  executionOrder: 0
-  icon: {instanceID: 0}
-  userData: 
-  assetBundleName: 
-  assetBundleVariant: 

Unity/Assets/Model/Entity/WWWAsync.cs

@@ -1,121 +0,0 @@
-using System;
-using System.Threading;
-using System.Threading.Tasks;
-using UnityEngine;
-
-namespace ETModel
-{
-	[ObjectSystem]
-	public class WwwAsyncUpdateSystem : UpdateSystem<WWWAsync>
-	{
-		public override void Update(WWWAsync self)
-		{
-			self.Update();
-		}
-	}
-	
-	public class WWWAsync: Entity
-	{
-		public WWW www;
-
-		public bool isCancel;
-
-		public ETTaskCompletionSource<bool> tcs;
-
-		public float Progress
-		{
-			get
-			{
-				if (this.www == null)
-				{
-					return 0;
-				}
-				return this.www.progress;
-			}
-		}
-
-		public int ByteDownloaded
-		{
-			get
-			{
-				if (this.www == null)
-				{
-					return 0;
-				}
-				return this.www.bytesDownloaded;
-			}
-		}
-
-		public void Update()
-		{
-			if (this.isCancel)
-			{
-				this.tcs.SetResult(false);
-				return;
-			}
-
-			if (!this.www.isDone)
-			{
-				return;
-			}
-
-			if (!string.IsNullOrEmpty(this.www.error))
-			{
-				this.tcs.SetException(new Exception($"WWWAsync error: {this.www.error}"));
-				return;
-			}
-
-			var t = this.tcs;
-			this.tcs = null;
-			t?.SetResult(true);
-		}
-
-		public ETTask<bool> LoadFromCacheOrDownload(string url, Hash128 hash)
-		{
-			url = url.Replace(" ", "%20");
-			this.www = WWW.LoadFromCacheOrDownload(url, hash, 0);
-			this.tcs = new ETTaskCompletionSource<bool>();
-			return this.tcs.Task;
-		}
-
-		public ETTask<bool> LoadFromCacheOrDownload(string url, Hash128 hash, CancellationToken cancellationToken)
-		{
-			url = url.Replace(" ", "%20");
-			this.www = WWW.LoadFromCacheOrDownload(url, hash, 0);
-			this.tcs = new ETTaskCompletionSource<bool>();
-			cancellationToken.Register(() => { this.isCancel = true; });
-			return this.tcs.Task;
-		}
-
-		public ETTask<bool> DownloadAsync(string url)
-		{
-			url = url.Replace(" ", "%20");
-			this.www = new WWW(url);
-			this.tcs = new ETTaskCompletionSource<bool>();
-			return this.tcs.Task;
-		}
-
-		public ETTask<bool> DownloadAsync(string url, CancellationToken cancellationToken)
-		{
-			url = url.Replace(" ", "%20");
-			this.www = new WWW(url);
-			this.tcs = new ETTaskCompletionSource<bool>();
-			cancellationToken.Register(() => { this.isCancel = true; });
-			return this.tcs.Task;
-		}
-
-		public override void Dispose()
-		{
-			if (this.IsDisposed)
-			{
-				return;
-			}
-
-			base.Dispose();
-
-            www?.Dispose();
-			this.www = null;
-			this.tcs = null;
-		}
-	}
-}

Unity/Assets/Model/Entity/WWWAsync.cs.meta

@@ -1,12 +0,0 @@
-fileFormatVersion: 2
-guid: 4d789ae4ba23a73469b228352499a1d0
-timeCreated: 1498117617
-licenseType: Free
-MonoImporter:
-  serializedVersion: 2
-  defaultReferences: []
-  executionOrder: 0
-  icon: {instanceID: 0}
-  userData: 
-  assetBundleName: 
-  assetBundleVariant: 

Unity/Unity.Model.csproj

@@ -55,16 +55,11 @@
   </ItemGroup>
   <ItemGroup>
     <Compile Include="Assets\Model\Base\Async\AsyncMethodBuilderAttribute.cs" />
-    <Compile Include="Assets\Model\Base\Async\AsyncUnit.cs" />
-    <Compile Include="Assets\Model\Base\Async\CancellationTokenExtensions.cs" />
     <Compile Include="Assets\Model\Base\Async\ETAsyncTaskMethodBuilder.cs" />
-    <Compile Include="Assets\Model\Base\Async\ETAsyncTaskVoidMethodBuilder.cs" />
     <Compile Include="Assets\Model\Base\Async\ETTask.cs" />
     <Compile Include="Assets\Model\Base\Async\ETTaskCompletionSource.cs" />
     <Compile Include="Assets\Model\Base\Async\ETTaskFactory.cs" />
-    <Compile Include="Assets\Model\Base\Async\ETTaskVoid.cs" />
     <Compile Include="Assets\Model\Base\Async\IAwaiter.cs" />
-    <Compile Include="Assets\Model\Base\Async\LazyPromise.cs" />
     <Compile Include="Assets\Model\Base\Async\MoveNextRunner.cs" />
     <Compile Include="Assets\Model\Base\DoubleMap.cs" />
     <Compile Include="Assets\Model\Base\Event\Env.cs" />
@@ -158,7 +153,6 @@
     <Compile Include="Assets\Model\Entity\Hotfix.cs" />
     <Compile Include="Assets\Model\Entity\Scene.cs" />
     <Compile Include="Assets\Model\Entity\UnityWebRequestAsync.cs" />
-    <Compile Include="Assets\Model\Entity\WWWAsync.cs" />
     <Compile Include="Assets\Model\Helper\ActionHelper.cs" />
     <Compile Include="Assets\Model\Helper\BundleHelper.cs" />
     <Compile Include="Assets\Model\Helper\GameObjectHelper.cs" />