Looping backreferences

[Brad Bowman]

> I would like (for no other reason than shorter lines and out of curiousity)
> to be able to more intuitively write
> $net = join ".", reverse $zone =~ /^(?:(\d+)\.){2,3}in-addr\.arpa$/;

Why not capture the whole "1.168.192"?

($_) = $zone =~ /^((?:\d+\.){2,3})in-addr\.arpa$/; 
$net = join '.', reverse split '\.';

It is more verbose but the {2,3} is preserved

> Anyone know if/how it's possible to have a variable-length list returned by 
> a regex? (preferably 5.6 compat)

I can't think of a way, but its not too hard to
list them out or build the regex with interpolation.

I thought maybe (??{}) could do it but it looks like
the capture grouping can't be deferred until runtime.
see
    perl -Mre=debug -e '/(...)/'
vs
    perl -Mre=debug -e '/(?{"(...)"})/'

Other ideas:

print $1 while /\G(\d+)\./g;

/(?: (\d+)\. (?{ print "$1\n" }) ){2,3}/x

1 while s/^(\d+)\.(.*)/$2.$1/;

Brad

-- 
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