Breakpoints within the text view

I’ve looked at some existing examples for adding breakpoint functionality using the CM view module. This works great in the case where breakpoints are always associated with distinct lines (i.e. each statement exists on separate lines). However, it is often useful to provide breakpoint functionality at a finer granularity (expression granularity), or to handle cases where multiple statements exist on a single line. I was wondering if there were any examples or suggestions on how to go about this. Thanks!