pan>
<a name="l00318"></a>00318   <span class="keyword">virtual</span> <span class="keyword">const</span> <span class="keywordtype">char</span>* toString() = 0;
<a name="l00319"></a>00319 
<a name="l00320"></a>00320   <span class="comment">// return parsed result as string.</span>
<a name="l00321"></a>00321   <span class="comment">// Result is saved in the buffer &#39;result&#39;, &#39;size&#39; is the</span>
<a name="l00322"></a>00322   <span class="comment">// size of the buffer. if failed, return NULL</s