It was possible to produce a regex that parses all of Perl, why not one for HTML?

There is a regex to parse XML (so, therefore, XHTML): XML Shallow Parsing

That regex produces a list of strings that will need further processing. Shallow parsing is mostly useful for XML-to-XML filtering. Technically, this challenge could be considered filtering, just not to XML. Will need to keep track of <div> nesting to find the end of the contained text.

# Not tested and assumes proper nesting of <div> elements (and valid X
+ML syntax)
# (Warning: Messy hack. Read at your own risk.)
my $nest = 0;
my $out = '';
my @elements = $xml =~ /$XML_SPE/g; # see http://www.cs.sfu.ca/~camero
+n/REX.html#AppA
for (@elements)
{
    if (/^<div/)
    {
        $nest++ if ($nest > 0); # only increment if inside an interest
+ing <div>
        next unless (/class\h*=\h*['"]data['"]/); # \h is horizontal w
+hite space
        next unless (/id\h*=\h*['"](\w+)['"]/);
        $out .= ", $1=";
        $nest = 1 if ($nest == 0); # if this is the outer most interes
+ting <div>
        next;
    }
    $nest--, next if (/^<\/div/);
    next if (/^[<]/); # skip other mark-up
    $out .= $_ if ($nest > 0);
}
$out =~ s/^, //;
say "$out\n";
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Update: Changed title to indicate (regex)