0) * close /
  function (s, o) return s end
</pre>

<p>
The <code>open</code> pattern matches <code>[=*[</code>,
capturing the repetitions of equal signs in a group named <code>init</code>;
it also discharges an optional newline, if present.
The <code>close</code> pattern matches <code>]=*]</code>,
also capturing the repetitions of equal signs.
The <code>closeeq</code> pattern first matches <code>close</code>;
then it uses a back capture to recover the capture made
by the previous <code>open</code>,
which i