Well, as I said, it was the e modifier I was missing. I had done plenty of searches and had indeed read various parts of perlretut such as

http://perldoc.perl.org/perlretut.html#A-bit-of-magic%3a-executing-Perl-code-in-a-regular-expression

and
http://groups.google.com/group/perl.beginners/browse_thread/thread/a11b27b5c5efb6ae

http://www.google.co.uk/search?sourceid=chrome&ie=UTF-8&q=regex+increment

Please could you suggest ways of searching for something in a way that answers the question when you are not exactly sure how to phrase the question. That would be better than telling me to read the documentation that I have just searched.

I thought the philosphy here was "A stupid question is an unasked question". Not "let me waste my time telling you to read the manual while I sit all smug because I know all the answers".

My apologies if I have misinterpreted your reply. Thank you very much for your helpful suggestions.

In reply to Re^2: Incremental replacement by regex by markdibley
in thread Incremental replacement by regex by markdibley

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