Can someone suggest to me what I'm doing wrong?

The .+ looks wrong, since it can match [[ and ]] too. You should use [^\]]+ in the first place.

Update: Here's a working regex: 

\[\[([^\]]+)]]

[download]

But it stops at a single ]. To prevent that, you need a negative look-ahead: 

\[\[((?:(?!\]\]).)+)]]

[download]

Now that's quite unreadable, so here in detail: 

\[\[            # opening delimiter
(               # capture...
  (?:           # a group
    (?!\]\])    #    that does not start with ]]
    .           #    and is a single character long
  )+            # and many of these groups, at least one.
)
]]              # closing delimiter

[download]
Perl 6 - second systems done right

In reply to Re: Regex question - negatives by moritz
in thread Regex question - negatives by ultranerds

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