Better handling of list.contains()

Upsilon/BaseTypes/ScriptIterator.cs

@@ -30,7 +30,10 @@ namespace Upsilon.BaseTypes
         }
 
         public abstract IEnumerator<ScriptType> GetScriptEnumerator();
-
+        public bool Contains(ScriptType obj)
+        {
+            return false;
+        }
     }
 
     internal class UpTillNullPairsScriptIterator : ScriptIterator

Upsilon/BaseTypes/ScriptTable/GenericKeyedScriptTable.cs

@@ -28,5 +28,10 @@ namespace Upsilon.BaseTypes.ScriptTable
                 yield return variable.Key.ToScriptType();
             }
         }
+
+        public override bool Contains(ScriptType obj)
+        {
+            return EvaluationScope.TryGet(obj.ToString(), out _);
+        }
     }
 }

Upsilon/BaseTypes/ScriptTable/NumeratedScriptTable.cs

@@ -19,6 +19,11 @@ namespace Upsilon.BaseTypes.ScriptTable
             }
         }
 
+        public override bool Contains(ScriptType obj)
+        {
+            return EvaluationScope.Variables.Values.Contains(obj);
+        }
+
 
         public override System.Type GetCSharpType()
         {

Upsilon/BaseTypes/ScriptTable/ScriptTable.cs

@@ -51,6 +51,7 @@ namespace Upsilon.BaseTypes.ScriptTable
         }
 
         public abstract IEnumerator<ScriptType> GetScriptEnumerator();
+        public abstract bool Contains(ScriptType obj);
 
         public ScriptNumberLong Length()
         {

Upsilon/BaseTypes/ScriptTypeInterfaces/IITerable.cs

@@ -6,5 +6,6 @@ namespace Upsilon.BaseTypes.ScriptTypeInterfaces
     {
         ScriptType GetValueFromIndex(ScriptType index);
         IEnumerator<ScriptType> GetScriptEnumerator();
+        bool Contains(ScriptType obj);
     }
 }

Upsilon/BaseTypes/UserData/DictionaryUserData.cs

@@ -108,5 +108,11 @@ namespace Upsilon.BaseTypes.UserData
             return (from object key in Dictionary.Keys
                 select key.ToScriptType()).GetEnumerator();
         }
+
+        public bool Contains(ScriptType obj)
+        {
+            var cSharpObj = obj.ToCSharpObject();
+            return Dictionary.Contains(cSharpObj);
+        }
     }
 }

Upsilon/BaseTypes/UserData/ListUserData.cs

@@ -138,6 +138,12 @@ namespace Upsilon.BaseTypes.UserData
             }
         }
 
+        public bool Contains(ScriptType obj)
+        {
+            var cSharpObj = obj.ToCSharpObject();
+            return List.Contains(cSharpObj);
+        }
+
         public ScriptNumberLong Length()
         {
             return new ScriptNumberLong(List.Count);

Upsilon/StandardLibraries/ListLibrary.cs

@@ -12,14 +12,7 @@ namespace Upsilon.StandardLibraries
         [ScriptFunction("contains", "Returns a boolean that defines whether a table contains a value", directScriptManipulation: true)]
         public ScriptBoolean Contains(IIterable table, ScriptType obj)
         {
-            var enumerator = table.GetScriptEnumerator();
+            return table.Contains(obj);
-            while (enumerator.MoveNext())
-            {
-                var current = enumerator.Current;
-                if (current == obj)
-                    return true;
-            }
-            return false;
         }
 
         [ScriptFunction("remove", "Removes an object from a table.", directScriptManipulation: true)]