1 files changed, 35 insertions, 0 deletions
diff --git a/src/mscorlib/shared/System/Action.cs b/src/mscorlib/shared/System/Action.cs
new file mode 100644
index 0000000000..b82c14d9dc
--- /dev/null
+++ b/src/mscorlib/shared/System/Action.cs
@@ -0,0 +1,35 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+namespace System
+{
+    public delegate void Action<in T>(T obj);
+
+    public delegate void Action();
+    public delegate void Action<in T1, in T2>(T1 arg1, T2 arg2);
+    public delegate void Action<in T1, in T2, in T3>(T1 arg1, T2 arg2, T3 arg3);
+    public delegate void Action<in T1, in T2, in T3, in T4>(T1 arg1, T2 arg2, T3 arg3, T4 arg4);
+
+    public delegate TResult Func<out TResult>();
+    public delegate TResult Func<in T, out TResult>(T arg);
+    public delegate TResult Func<in T1, in T2, out TResult>(T1 arg1, T2 arg2);
+    public delegate TResult Func<in T1, in T2, in T3, out TResult>(T1 arg1, T2 arg2, T3 arg3);
+    public delegate TResult Func<in T1, in T2, in T3, in T4, out TResult>(T1 arg1, T2 arg2, T3 arg3, T4 arg4);
+
+    public delegate void Action<in T1, in T2, in T3, in T4, in T5>(T1 arg1, T2 arg2, T3 arg3, T4 arg4, T5 arg5);
+    public delegate void Action<in T1, in T2, in T3, in T4, in T5, in T6>(T1 arg1, T2 arg2, T3 arg3, T4 arg4, T5 arg5, T6 arg6);
+    public delegate void Action<in T1, in T2, in T3, in T4, in T5, in T6, in T7>(T1 arg1, T2 arg2, T3 arg3, T4 arg4, T5 arg5, T6 arg6, T7 arg7);
+    public delegate void Action<in T1, in T2, in T3, in T4, in T5, in T6, in T7, in T8>(T1 arg1, T2 arg2, T3 arg3, T4 arg4, T5 arg5, T6 arg6, T7 arg7, T8 arg8);
+
+    public delegate TResult Func<in T1, in T2, in T3, in T4, in T5, out TResult>(T1 arg1, T2 arg2, T3 arg3, T4 arg4, T5 arg5);
+    public delegate TResult Func<in T1, in T2, in T3, in T4, in T5, in T6, out TResult>(T1 arg1, T2 arg2, T3 arg3, T4 arg4, T5 arg5, T6 arg6);
+    public delegate TResult Func<in T1, in T2, in T3, in T4, in T5, in T6, in T7, out TResult>(T1 arg1, T2 arg2, T3 arg3, T4 arg4, T5 arg5, T6 arg6, T7 arg7);
+    public delegate TResult Func<in T1, in T2, in T3, in T4, in T5, in T6, in T7, in T8, out TResult>(T1 arg1, T2 arg2, T3 arg3, T4 arg4, T5 arg5, T6 arg6, T7 arg7, T8 arg8);
+
+    public delegate int Comparison<in T>(T x, T y);
+
+    public delegate TOutput Converter<in TInput, out TOutput>(TInput input);
+
+    public delegate bool Predicate<in T>(T obj);
+}