(swift-markdown): how to “abort” markup rewriting?

i’m trying to trim off the leading aside header from a ListItem, such as foo in

- `foo`:
   some more text in this list item

or see also (without backticks) in

- see also:
   some more text in this list item

since the list item can be much longer than the aside heading, is there a way to implement MarkupRewriter in a way that stops traversing markup once it encounters a colon? (or soft line break)