diff --git a/test/isn.tests/Engine.cs b/test/isn.tests/Engine.cs
new file mode 100644
index 0000000..74627c5
--- /dev/null
+++ b/test/isn.tests/Engine.cs
@@ -0,0 +1,17 @@
+using static isn.tests.Tests;
+
+namespace isn.tests
+{
+    internal class Engine : INeedEngine
+    {
+        public Engine()
+        {
+
+        }
+
+        public object Parse(string code)
+        {
+            throw new System.NotImplementedException();
+        }
+    }
+}
\ No newline at end of file
diff --git a/test/isn.tests/IBody.cs b/test/isn.tests/IBody.cs
new file mode 100644
index 0000000..2869069
--- /dev/null
+++ b/test/isn.tests/IBody.cs
@@ -0,0 +1,12 @@
+namespace isn.tests
+{
+    internal interface IBody
+    {
+        /// <summary>
+        /// The mult 
+        /// </summary>
+        /// <returns></returns>
+        T Action<T>(T v);
+
+    }
+}
\ No newline at end of file
diff --git a/test/isn.tests/IRing.cs b/test/isn.tests/IRing.cs
new file mode 100644
index 0000000..026a637
--- /dev/null
+++ b/test/isn.tests/IRing.cs
@@ -0,0 +1,11 @@
+namespace isn.tests
+{
+    internal interface IRing : IBody
+    {
+
+
+        IRing Add(IRing other);
+        IRing Mult<TBody>(TBody v);
+    }
+
+}
\ No newline at end of file
diff --git a/test/isn.tests/Ring.cs b/test/isn.tests/Ring.cs
new file mode 100644
index 0000000..0089db7
--- /dev/null
+++ b/test/isn.tests/Ring.cs
@@ -0,0 +1,29 @@
+namespace isn.tests
+{
+    internal class Body : IBody
+    {
+        static public Ring One { get ;}
+
+        public T Action<T>(T v)
+        {
+            throw new System.NotImplementedException();
+        }
+
+    }
+    internal class Ring : Body, IRing
+    {
+        public static IRing Zero => throw new System.NotImplementedException();
+
+
+        public IRing Add(IRing unity)
+        {
+            throw new System.NotImplementedException();
+        }
+
+        public IRing Mult<TBody>(TBody v)
+        {
+            throw new System.NotImplementedException();
+        }
+
+    }
+}
\ No newline at end of file
diff --git a/test/isn.tests/UnitTest1.cs b/test/isn.tests/UnitTest1.cs
index bbce537..946718a 100644
--- a/test/isn.tests/UnitTest1.cs
+++ b/test/isn.tests/UnitTest1.cs
@@ -5,6 +5,15 @@ namespace isn.tests
 {
     public class Tests
     {
+        private const int V = 0;
+        private const int V1 = 1;
+
+        public interface INeedEngine
+        {
+            object Parse(string code);
+
+        }
+
         [SetUp]
         public void Setup()
         {
@@ -22,7 +31,7 @@ namespace isn.tests
             Assert.Pass();
         }
 
-        
+
         [Test]
         public void Test26()
         {
@@ -34,6 +43,26 @@ namespace isn.tests
             Assert.AreEqual(pass, unprotectedpass);
             Assert.Pass();
         }
+        public void TestParseCplus()
+        {
+            INeedEngine engine = new Engine();
+            IRing c = new Ring();
+            Assert.Equals((INeedEngine)engine.Parse("c+"), c.Add(Ring.One));
+        }
+
+        public void AssertIRingIsABody()
+        {
+            Ring c = new Ring();
+            Ring one = Ring.One;
+            Assert.True(c.Mult(one).Equals(c));
+        }
+        public void AssertIRingIsARing()
+        {
+            AssertIRingIsABody();
+            Ring c = new Ring();
+            IRing zero = Ring.Zero;
+            Assert.True(c.Add(zero).Equals(c));
+        }
 
     }
 }
\ No newline at end of file