Doing it in a single regexp is possible, although it won't be what you're looking at: 
s{.*}
{              xx
             xxxx
            xxxxxx
           xxxxxxxx
          xxxxxxxxxx
         xxxxxxxxxxxx
        xxxxxxxxxxxxxx
       xxxxxxxxxxxxxxxx
      xxxxxxxxxxxxxxxxxx
     xxxxxxxxxxxxxxxxxxxx
    xxxxxxxxxxxxxxxxxxxxxx
   xxxxxxxxxxxxxxxxxxxxxxxx
  xxxxxxxxxxxxxxxxxxxxxxxxxx
 xxxxxxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
              xx
              xx}s;

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In reply to Re: Resetting pos() within a RegEx? by JavaFan
in thread Resetting pos() within a RegEx? by LanX

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