(_ unicodeScalarIndex: UnicodeScalarIndex, within utf16: String.UTF16View)</code>

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<a class="toggle-link" data-toggle="collapse" href="#comment-init_within_">init?(<wbr>_:<wbr>within:)</a><div class="comment collapse" id="comment-init_within_"><div class="p">
    <p>Construct the position in <code>utf16</code> that corresponds exactly to
<code>utf8Index</code>. If no such position exists, the result is <code>nil</code>.</p>

<p><strong>Requ