Well, the problem isn't very well defined. All you give is an example. So, I'm taking some liberties on the precise specification of how the "tags" may appear.

Assuming your text is stored in $_, you can do it in two lines. First line grabs the YYY info, second line substitutes the XXX. You may have to tweak the regexes depending on the precise specification. 

    my %data = m!<X-REF REFID="([^"]+)">([^<]+)</XREF>!g;
    s!<FTN ID="([^"]+)">[^<]+</FTN>!<FTN ID="$1">$data{$1}</FTN>!g;

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Abigail

In reply to Re: replacing text in specific tags by Abigail-II
in thread replacing text in specific tags by texuser74

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