span>&nbsp;<span class="constructor">Compiler_pass</span>&nbsp;:<br>
&nbsp;&nbsp;&nbsp;&nbsp;<span class="keyword">sig</span><br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="keyword">type</span>&nbsp;t&nbsp;=&nbsp;<span class="constructor">Parsing</span>&nbsp;<span class="keywordsign">|</span>&nbsp;<span class="constructor">Typing</span><br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="keyword">val</span>&nbsp;of_string&nbsp;:&nbsp;string&nbsp;<span class="keywordsign">-&gt;</span>&nbsp;<span class