;~src_pos&nbsp;~dst&nbsp;~dst_pos&nbsp;~len</code> copies <code class="code">len</code> bytes from string
    <code class="code">src</code>, starting at index <code class="code">src_pos</code>, to byte sequence <code class="code">dst</code>,
    starting at index <code class="code">dst_pos</code>.</p>
</div>
<ul class="info-attributes">
<li><b>Since</b> 4.05.0 in BytesLabels</li>
<li><b>Raises</b> <code>Invalid_argument</code> if <code class="code">src_pos</code> and <code class="code">len</code> do not
   