Yikes ! This gave me an opportunity to learn a bit about debuggering regex.

The pragma use re 'debug' will tell you more than you ever thought you might have wanted to know about the regex being processed.

The problem I found was that the 'colts' html contains:

  <td class="qty" style="width: 7%;">
where your regex was looking for:
  <td class="qty">
Because the regex is littered with .*?, there is lots of scope for backtracking. As far as I can see:

I doubt that this is an infinite loop. But I haven't the patience to establish one way or the other.

Not sure what to suggest here... Where possible I would replace .*? by, for example, [^<]*? -- which limits the scope for backtracking. There is other regex magic to limit backtracking, but I'm not familiar with it.

However, the big problem I see is that you can never be sure whether your regex has failed because there is no more data of interest, or because it's not recognising a small variation in format. Do you have a drawing board ?

In reply to Re^5: Regex infinite loop? by gone2015
in thread Regex infinite loop? by Ninth Prince

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