Implement IEnumerable<T>

Collections/ImmutableStack.cs

@@ -1,9 +1,48 @@
 using System;
+using System.Collections;
+using System.Collections.Generic;
 
 namespace ModuleManager.Collections
 {
-    public class ImmutableStack<T>
+    public class ImmutableStack<T> : IEnumerable<T>
     {
+        public struct Enumerator : IEnumerator<T>
+        {
+            private ImmutableStack<T> head;
+            private ImmutableStack<T> currentStack;
+
+            public Enumerator(ImmutableStack<T> stack)
+            {
+                head = stack;
+                currentStack = null;
+            }
+
+            public T Current => currentStack.value;
+            object IEnumerator.Current => Current;
+
+            public void Dispose() { }
+
+            public bool MoveNext()
+            {
+                if (currentStack == null)
+                {
+                    currentStack = head;
+                    return true;
+                }
+                else if (!currentStack.IsRoot)
+                {
+                    currentStack = currentStack.parent;
+                    return true;
+                }
+                else
+                {
+                    return false;
+                }
+            }
+
+            public void Reset() => currentStack = null;
+        }
+
         public readonly T value;
         public readonly ImmutableStack<T> parent;
 
@@ -33,5 +72,9 @@ public ImmutableStack<T> Pop()
         }
 
         public ImmutableStack<T> ReplaceValue(T newValue) => new ImmutableStack<T>(newValue, parent);
+
+        public Enumerator GetEnumerator() => new Enumerator(this);
+        IEnumerator<T> IEnumerable<T>.GetEnumerator() => GetEnumerator();
+        IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
     }
 }

Extensions/NodeStackExtensions.cs

@@ -0,0 +1,26 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using NodeStack = ModuleManager.Collections.ImmutableStack<ConfigNode>;
+
+namespace ModuleManager.Extensions
+{
+    public static class NodeStackExtensions
+    {
+        public static string GetPath(this NodeStack stack)
+        {
+            int length = stack.Sum(node => node.name.Length) + stack.Depth - 1;
+            StringBuilder sb = new StringBuilder(length);
+
+            foreach (ConfigNode node in stack)
+            {
+                string nodeName = node.name;
+                sb.Insert(0, node.name);
+                if (sb.Length < sb.Capacity) sb.Insert(0, '/');
+            }
+
+            return sb.ToString();
+        }
+    }
+}