Example code: 
my $string = q(
Outside.
{tag}
Inside level 1.
{tag}
Inside level 2.
{/tag}
Inside level 1.
{/tag}
Outside.
);

$string =~ s/\{tag\}(.+)\{\/tag\}/--Marked--\n$1\n--EndMarked--/gis;
Right, so that matches the first {tag} and the last {/tag}. But nothing inbetween. If I change the pattern to 
/\{tag\}(.+?)\{\/tag\}/
it matches the first {tag} and the first {/tag}, but because the second {tag} was inside the block just matched, it's passed over when seeking the next {tag}.

Le sigh.

The only way I can find to get this thing working as desired is to wrap the pattern match in a while loop: 
while($string =~ s/\{tag\}(.+)\{\/tag\}/--Marked--\n$1\n--EndMarked--/gis) { next; }
That's a sub-optimal solution for the problem at hand, where there are dozens of these specialized markup tags.

Is there a better/quicker/easier way to get this done? Use of *ANY* module not standard in 5.004 is out of the question due to the needs of the app's audience. (I was looking at Parse::RecDecent...)

I thank you for your wisdom.

In reply to Properly transforming strings with nested markup tags by tocie

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