 starting at index <code class="code">src_pos</code>,
    to byte sequence <code class="code">dst</code>, starting at character number <code class="code">dst_pos</code>.</p>
</div>
<ul class="info-attributes">
<li><b>Raises</b> <code>Invalid_argument</code> if <code class="code">src_pos</code> and <code class="code">len</code> do not
    designate a valid range of <code class="code">src</code>, or if <code class="code">dst_pos</code> and <code class="code">len</code>
    do not designate a valid range of <c