following example <code>+Any</code> is used simply for the reason that
there is no direct way to specify dotted pairs:

<pre>
(rel loc (+Any))  # Locale, e.g. ("DE" . "de")
</pre></dd>

<dt><a id="+Aux"><code>+Aux</code></a></dt>
<dd>Prefix class maintaining auxiliary keys for <code><a
href="refR.html#+relation">+relation</a></code>s, in addition to <code><a
href="refR.html#+Ref">+Ref</a></code> or <code><a
href="refI.html#+Idx">+Idx</a></code> indexes. Expects a list of auxiliary
attributes of the same obj