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From: Stefan Monnier <monnier@iro.umontreal.ca>
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Subject: Re: Structural regular expressions
Date: Fri, 10 Sep 2010 15:31:03 +0200
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To: David Kastrup <dak@gnu.org>
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>>> And what is narrow-to-region supposed to do then?
>> Signal an error when the region is not contiguous?
> Opens another can of worms because quite a number of commands accepting
> a region argument implement it internally using narrow-to-region.

What can of worms?  Old uses will still work just as well as before.

And as explained in earlier threads, some of those commands could be
magically made to work by letting an "r" in the interactive spec mean
"apply once per contiguous region segment".  I haven't experimented with
such a change, so it may or may not be an acceptable heuristic, but in
any case I don't see it as a problem that commands need to be adjusted
in order to work in the case that the region is split into more than
1 chunk.


        Stefan