desc">
<p><code class="code">index_opt&nbsp;s&nbsp;c</code> is <a href="String.html#VALindex_from_opt"><code class="code"><span class="constructor">String</span>.index_from_opt</code></a><code class="code">&nbsp;s&nbsp;0&nbsp;c</code>.</p>
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<ul class="info-attributes">
<li><b>Since</b> 4.05</li>
</ul>
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<pre><span id="VALrindex"><span class="keyword">val</span> rindex</span> : <code class="type">string -&gt; char -&gt; int</code></pre><div class="info ">
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<p><code class="c