Given the lack of restrains in the text to parse, this might be impossible to get right all the time. You already pointed out the difficulty (or rather, impossibleness) of determining whether i is a Roman numeral, or a Latin letter. To complicate things further, both i and a are ordinary English words. vi is the name of an editor, and xi is an uncommon, but not impossible, English word. And so is li.

Abigail

In reply to Re: Matching indented paragraph numbering with regexps by Abigail-II
in thread Matching indented paragraph numbering with regexps by AndyH

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