- textual-length textualprocedure
- textual-ref textual idxprocedure
textual-length returns the number of characters in textual, and textual-ref returns the character at character index idx, using 0-origin indexing. These procedures are the generalizations of text-length and text-ref to accept strings as well as texts. If textual is a text, they must execute in O(1) time, but there is no such requirement if textual is a string.