Monodevelop Does not Access List or IEnumerator?

Google 'c# list' and follow the first link, which is almost always going to take you to a page on the Microsoft Developer Network. When you get there look for the namespace and you'll see it's System.Collections.Generic, so just add 'using System.Collections.Generic' at the top of your script, following the default 'using' statements that you'll find there.

Repeat for IEnumerator and you'll find it's in System.Collections, which is actually there by default. In this case, I think you should check your spelling of IEnumerator. I only say this because you have a typo in it in your question's title, so you may have the same one in your script too.

I also faced this problem. make sure that you inherit MonoBehaviour in your class. without that LIst will not show in unity.

http://www.dotnetperls.com/list < dotnetperls is a great C# reference.. they take you step by step and explain whats going on. I used this early on when the msdn docs were a bit to much to handle, but anyway here is a working example of a list to try and to compare to:

 using UnityEngine;
 using System.Collections;
 using System.Collections.Generic;
 
     public class ListExample : MonoBehaviour {
     
         List<int> myInts = new List<int>();
     
         bool print = true;
         // Use this for initialization
         void Start () {
             myInts.Add(1);
             myInts.Add(99);
             myInts.Add(208);
         }
     
         static IEnumerable<int> YieldReturn()
         {
             yield return 1;
             yield return 2;
             yield return 3;
         }
     
         
         // Update is called once per frame
         void Update () {
             if(print)
             {
                 foreach(int myInt in myInts)
                 {
                     Debug.Log("my List values: " + myInt);
                 }
     
                 foreach (int i in YieldReturn())
                 {
                     Debug.Log("My IEnumerable values: " + i);
                 }
     
                 print = false;
             }
         }
     }

http://stackoverflow.com/questions/3628425/ienumerable-vs-list-what-to-use-how-do-they-work < also another great reference for IEnumerable vs Lists

If you place the above code in a new scene on a game object you should see whats expected. list will print 1, 99, and 208. while ienuerable will print 1,2,3 GL!