Merge branch 'feat/monad-completion-source' into 'develop'

Monad completion source

See merge request engine/mast!9

Assets/Plugins/Rayark/Mast/Editor/Tests/TestMonad.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections;
+using System.Threading;
 using NUnit.Framework;
 
 namespace Rayark.Mast
@@ -659,5 +660,45 @@ public void FuncMonadTest2()
             Assert.IsNotNull(m.Error);
             Assert.AreEqual("ex", m.Error.Message);
         }
+
+        [Test]
+        public void MonadCompletionSourceTest()
+        {
+            var mcs = new MonadCompletionSource<int>();
+            var m = mcs.Monad;
+
+            _MonadCompletionSourceTestTask1(mcs);
+            _Wait(m);
+            Assert.AreEqual(3, m.Result);
+        }
+
+        void _MonadCompletionSourceTestTask1(IReturn<int> r)
+        {
+            ThreadPool.QueueUserWorkItem( state =>
+            {
+                Thread.Sleep(500);
+                r.Accept(3);              
+            });
+        }
+
+        [Test]
+        public void MonadCompletionSourceErrorTest()
+        {
+            var mcs = new MonadCompletionSource<int>();
+            var m = mcs.Monad;
+
+            _MonadCompletionSourceTestTask2(mcs);
+            _Wait(m);
+            Assert.AreEqual(typeof(ArgumentException), m.Error.GetType());
+        }
+
+        void _MonadCompletionSourceTestTask2(IReturn<int> r)
+        {
+            ThreadPool.QueueUserWorkItem( state =>
+            {
+                Thread.Sleep(500);
+                r.Fail(new ArgumentException());              
+            });
+        }
     }
 }

Assets/Plugins/Rayark/Mast/MonadCompletionSource.cs

@@ -0,0 +1,75 @@
+using System;
+using System.Collections;
+
+namespace Rayark.Mast
+{
+    /// <summary>
+    /// Represents the producer side of a <see cref="IMonad{T}"/> unbound to a coroutine,
+    /// providing access to the consumer side through the Monad property. 
+    /// </summary>
+    /// <typeparam name="T">The type of the result value associated with this <see cref="MonadCompletionSource{T}"/></typeparam>
+    public class MonadCompletionSource<T> : IReturn<T>
+    {
+
+        #region private types
+        private class InternalMonad : IMonad<T>, IEnumerator
+        {
+            public bool IsDone = false;
+
+            public T Result
+            {
+                get;
+                set;
+            }
+
+            public Exception Error
+            {
+                get;
+                set;
+            }
+            public IEnumerator Do()
+            {
+                return this;
+            }
+
+            public bool MoveNext()
+            {
+                return !IsDone;
+            }
+
+            public void Reset()
+            {
+            }
+
+            public object Current
+            {
+                get { return null; }
+            }
+        }
+        #endregion
+
+
+        readonly InternalMonad _monad = new InternalMonad();
+
+        public IMonad<T> Monad
+        {
+            get { return _monad; }
+        }
+
+        public void Accept(T result)
+        {
+            if (_monad.IsDone)
+                throw new System.Exception("Already done");
+            _monad.Result = result;
+            _monad.IsDone = true;
+        }
+
+        public void Fail(Exception error)
+        {
+            if (_monad.IsDone)
+                throw new System.Exception("Already done");
+            _monad.Error = error;
+            _monad.IsDone = true;
+        }
+    }
+}