diff --git a/Upsilon/BaseTypes/ScriptFunction/ScriptRuntimeFunction.cs b/Upsilon/BaseTypes/ScriptFunction/ScriptRuntimeFunction.cs
index 1132449..bd18d2b 100644
--- a/Upsilon/BaseTypes/ScriptFunction/ScriptRuntimeFunction.cs
+++ b/Upsilon/BaseTypes/ScriptFunction/ScriptRuntimeFunction.cs
@@ -93,6 +93,36 @@ namespace Upsilon.BaseTypes.ScriptFunction
             return null;
         }
 
+        public void AddOption(ScriptRuntimeFunctionOption newOption)
+        {
+            var variables = newOption.Parameters;
+            for (var i = 0; i < Options.Count; i++)
+            {
+                var option = Options[i];
+                if (option.Parameters.Length != variables.Length)
+                    continue;
+                bool isCompatible = true;
+                for (var index = 0; index < variables.Length; index++)
+                {
+                    var callingVariable = variables[index];
+                    var optionVariable  = option.Parameters[index];
+                    if (callingVariable.Type == BaseTypes.Type.Unknown || callingVariable.Type == BaseTypes.Type.Nil ||
+                        optionVariable.Type  == BaseTypes.Type.Unknown)
+                        continue;
+                    if (callingVariable.Type != optionVariable.Type)
+                    {
+                        isCompatible = false;
+                        break;
+                    }
+                }
+                if (!isCompatible)
+                    continue;
+                Options[i] = newOption;
+                break;
+            }
+            Options.Add(newOption);
+        }
+
 
         public class ScriptRuntimeFunctionOption : IScopeOwner
         {
diff --git a/Upsilon/Evaluator/Evaluator.cs b/Upsilon/Evaluator/Evaluator.cs
index efa004a..1fbb9fd 100644
--- a/Upsilon/Evaluator/Evaluator.cs
+++ b/Upsilon/Evaluator/Evaluator.cs
@@ -501,7 +501,7 @@ namespace Upsilon.Evaluator
             {
                 if (Scope.Variables.TryGetValue(e.Variable.Name, out var f) && f is ScriptRuntimeFunction scriptRuntimeFunction)
                 {
-                    scriptRuntimeFunction.Options.AddRange(func.Options);
+                    scriptRuntimeFunction.AddOption(func.Options[0]);
                 }
                 else
                 {
@@ -512,7 +512,7 @@ namespace Upsilon.Evaluator
             {
                 if (Scope.TryGet(e.Variable, out var f) && f is ScriptRuntimeFunction scriptRuntimeFunction)
                 {
-                    scriptRuntimeFunction.Options.AddRange(func.Options);
+                    scriptRuntimeFunction.AddOption(func.Options[0]);
                 }
                 else
                 {