nbsp;&nbsp;&nbsp;&nbsp;<span class="keyword">val</span>&nbsp;(&nbsp;//&nbsp;)&nbsp;:&nbsp;<span class="constructor">Dir</span>.t&nbsp;<span class="keywordsign">-&gt;</span>&nbsp;string&nbsp;<span class="keywordsign">-&gt;</span>&nbsp;t<br>
&nbsp;&nbsp;&nbsp;&nbsp;<span class="keyword">end</span><br>
&nbsp;&nbsp;<span class="keyword">module</span>&nbsp;<span class="constructor">Attribute</span>&nbsp;:<br>
&nbsp;&nbsp;&nbsp;&nbsp;<span class="keyword">sig</span><br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span c