diff --git a/todo.md b/todo.md
index 0d06c67..2bfb1b9 100644
--- a/todo.md
+++ b/todo.md
@@ -13,4 +13,6 @@
     - ~~inner~~
     - ~~attributes~~
     - ~~node~~
-    - tests for all of it
\ No newline at end of file
+    - tests for all of it
+- substring out of range?
+    - test it
\ No newline at end of file