hope this helps:
perl -i -pe 'if (/<level1 id=\"(.*)\">/) {$currentid = $1;} elsif (/<level2>/) {s/<level2>/<level2 id="$currentid">/g}' input

edit: just deleting the redundant $_.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"one who asks a question is a fool for five minutes; one who does not ask a question remains a fool forever."

mk at rio dot pm dot org

In reply to Re: Regex problem while parsing tagged, hierarchical data by mk.
in thread Regex problem while parsing tagged, hierarchical data by sivaramanm

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