sp;[OP_VARIABLE]
 [4]
 [index to namespace token, or EMPTY]
 [index to function name token]

 returns:
  XString</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>static&nbsp;int</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../../org/apache/xpath/compiler/OpCodes.html#OP_XPATH">OP_XPATH</A></B></CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[OP_XPATH]
 [length]
  {expression}

 returns:
  XNodeSet
  XNumber
  XS