"): "<tt>expr</tt>",
  "<tt>patt</tt>", "<tt>expr</tt>", "<tt>str_item</tt>",
  "<tt>sig_item</tt>", and so on. All syntax parts of these types are
  automatically antiquotable.</p>

<p>For example, in Camlp5 sources, the grammar rule defining the
  "let..in" statement is:</p>

<pre>
   "let"; r = V (FLAG "rec") "flag" "opt";
    l = V (LIST1 let_binding SEP "and"); "in"; x = expr
</pre>

<p>All symbols of these rules, except the keywords, are antiquotable:</p>

<ul>
  <li>The "rec" flag, because enclosed b