r">optimize</span><span class="special">;</span>
  <span class="keyword">static</span> <span class="identifier">regex_constants</span><span class="special">::</span><span class="identifier">syntax_option_type</span> <span class="keyword">const</span> <span class="identifier">collate</span><span class="special">;</span>
  <span class="keyword">static</span> <span class="identifier">regex_constants</span><span class="special">::</span><span class="identifier">syntax_option_type</span> <span class="keyword">co