So let's see if I understand this and please correct me if I'm wrong.

The ?: means that the parens are just for grouping and will load any matches into $1, $2, etc.
Then the character class in parens
and then the lookahead...
?! means that it is a negative lookahead
.* means any character 0 or more times (very greedy)
\1 is related to the character matched from the character class
It's the .* that is throwing me off. To me, that looks like it would match a single character repeated any number of times but not separated duplicate characters. I just don't understand it ... yet. I will keep looking.

In reply to Re: Re: Re: Regex (lookahead) Confusion by ChrisR
in thread Regex (lookahead) Confusion by ChrisR

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