e"></a><span class="identifier">string_type</span><span class="special">;</span>  <span class="comment">// String type to be used as a message text holder. </span>
  <span class="keyword">typedef</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span> <span class="identifier">char_type</span> <span class="special">&gt;</span> <a name="boost.log.sinks.basic_text_ostream_backend.stream_type"></a><span class="identi