1 files changed, 6 insertions, 1 deletions
diff --git a/PureData/PureData.cs b/PureData/PureData.cs
index c9ac143..6e55693 100644
--- a/PureData/PureData.cs
+++ b/PureData/PureData.cs
@@ -15,7 +15,7 @@ namespace PureData
     }
     
     // This is the base class for a PD/CLR external
-    public unsafe class External
+    public unsafe abstract class External
     {
         // PD object pointer
         private readonly void *ptr;
@@ -59,6 +59,11 @@ namespace PureData
         protected extern static void Add(MethodList m);
 
         [MethodImplAttribute (MethodImplOptions.InternalCall)]
+        protected extern static void Add(Symbol sel,MethodList m);
+
+        protected static void Add(string sel,MethodList m) { Add(new Symbol(sel),m); }
+
+        [MethodImplAttribute (MethodImplOptions.InternalCall)]
         protected extern static void Add(MethodAnything m);
     }
 }