sp;string<br>
&nbsp;&nbsp;<span class="keyword">val</span>&nbsp;escaped&nbsp;:&nbsp;string&nbsp;<span class="keywordsign">-&gt;</span>&nbsp;string<br>
&nbsp;&nbsp;<span class="keyword">val</span>&nbsp;index&nbsp;:&nbsp;string&nbsp;<span class="keywordsign">-&gt;</span>&nbsp;char&nbsp;<span class="keywordsign">-&gt;</span>&nbsp;int<br>
&nbsp;&nbsp;<span class="keyword">val</span>&nbsp;index_opt&nbsp;:&nbsp;string&nbsp;<span class="keywordsign">-&gt;</span>&nbsp;char&nbsp;<span class="keywordsign">-&gt;</span