n><span class="identifier">size_t</span>
<span class="identifier">find_first_of</span><span class="special">(</span>
    <span class="identifier">string_view</span> <span class="identifier">sv</span><span class="special">,</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">pos</span> <span class="special">=</span> <span class="number">0</span><span class="special">)</span> <span class="keyword">const</span><span class=