pecial">&lt;</span> <span class="identifier">char_type</span> <span class="special">&gt;</span> <span class="keyword">const</span> <span class="special">&amp;</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
  <span class="identifier">string_type</span> <a class="link" href="c_regex_traits.html#idp115383104-bb"><span class="identifier">fold_case</span></a><span class="special">(</span><span class="identifier">char_type</span><span class="special">)</span>