Greetings to all

I need to process two (and possibly a third) group of patterns in my input . My current code snippet for this is:

while ($data_in =~ /<container><a>(.+?)<\/a><b>(.+?)<\/b><\/container>
+(<\?query\?>)??/ig)  {
  $data_out = "$2, $1$3 ";  errors here
  ; further processing here 
}

[download]

However I am getting this error: 'Use of uninitialized value in concatenation (.) or string' referring I believe to $3 when it does not exist.

I did try the following:

while ($data_in =~ /<container><a>(.+?)<\/a><b>(.+?)<\/b><\/container>
+(<\?query\?>)??/ig)  {
  if ($+ =~ /<\?query\?>/i) {;   errors here now
    $data_out = "$2, $1$3 ";
    } else {
    $data_out = "$2, $1 ";
    }
  ; further processing here 
}

[download]

But then I get this:
Use of uninitialized value in pattern match (m//)

Of course there is probably a much simpler way of achieving this.

Thanks for any advice
fiat

In reply to Special Variables in Regular Expression by fiat

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