System.Collections.Stack.Enumerator.MoveNext C# (CSharp) Method

			public virtual bool MoveNext() {
				if (modCount != stack.modCount)
					throw new InvalidOperationException();
				
				switch (current) {
				case BOF:
					current = stack.current;
					return current != -1;
				
				case EOF:
					return false;
				
				default:
					current--; 
					return current != -1;
				}
			}