Mono.CSharp.ToplevelBlock.AddLocalName C# (CSharp) Method

		public override void AddLocalName (string name, INamedBlockVariable li)
		{
			if (names == null)
				names = new Dictionary<string, object> ();

			object value;
			if (!names.TryGetValue (name, out value)) {
				names.Add (name, li);
				return;
			}

			INamedBlockVariable existing = value as INamedBlockVariable;
			List<INamedBlockVariable> existing_list;
			if (existing != null) {
				existing_list = new List<INamedBlockVariable> ();
				existing_list.Add (existing);
				names[name] = existing_list;
			} else {
				existing_list = (List<INamedBlockVariable>) value;
			}

			//
			// A collision checking between local names
			//
			for (int i = 0; i < existing_list.Count; ++i) {
				existing = existing_list[i];
				Block b = existing.Block;

				// Collision at same level
				if (li.Block == b) {
					li.Block.Error_AlreadyDeclared (name, li);
					break;
				}

				// Collision with parent
				b = li.Block;
				while ((b = b.Parent) != null) {
					if (existing.Block == b) {
						li.Block.Error_AlreadyDeclared (name, li, "parent or current");
						i = existing_list.Count;
						break;
					}
				}

				// Collision with with children
				b = existing.Block;
				while ((b = b.Parent) != null) {
					if (li.Block == b) {
						li.Block.Error_AlreadyDeclared (name, li, "child");
						i = existing_list.Count;
						break;
					}
				}
			}

			existing_list.Add (li);
		}