I wouldn't do that with a (single) regex at all. There are tons of other ways: in particular in this case your data seems fairly regular. Thus one possibility (and just one amongst the may WTDI) may be:

1. read in by paragraphs;
2. split on \n;
3. parse the single lines to get, say, ($data, $value);
4. use a hash:

   my %defult = (what => 'wtf?', date => 'no date', data => 'no data');
   # ...
   unless (exists $default{$data}) {
       warn "unexpected field: $data'";
       # ...
   }
   $value ||= $default{$data};
   [download]

Of course //= would be better suited for this, but since we currently don't have it yet unless we installed a patch, ||= should be enough. If it is not or in case of doubt, use your own defined test instead.

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