rd">public</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">runtime_error</span>, <span class="keyword">public</span> <span class="identifier">exception</span> <span class="special">{</span>
  <span class="comment">// <a class="link" href="regex_error.html#boost.xpressive.regex_errorconstruct-copy-destruct">construct/copy/destruct</a></span>
  <span class="keyword">explicit</span> <a class="link" href="regex_error.html#id-1_3_47_5_7_2_1_1_5-bb"><span class="i