I saw this and was going to reply with something to the effect of Set::IntSpan but I was too late and mine wouldn't have had as clever a trick with that closure coderef . . . bah.

Also as far as the original question, IMHO most times if you're thinking about embedding code inside your regexen you're pretty well already deep into (quasi-apocryphical) JWZ-quote / xkcd 1171 territory.

The cake is a lie.
The cake is a lie.
The cake is a lie.

In reply to Re^2: Regexp substitution on variable-length ranges with embedded code? by Fletch
in thread Regexp substitution on variable-length ranges with embedded code? by Polyglot

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