> So, is there a way to use capture groups to match multiple times like separate groups does in the first example?

It depends what your goal is.

If it's simply using a quantifier {4} the answer is no, because only the last match will be kept for the unique first group , that's why you get 01D9 at the end. Not a mystery.

But there are numerous workarounds I can think of.

Like

updates

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re: mysteries of regex substring matching by LanX
in thread mysteries of regex substring matching by smile4me

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