code: Rule IfieldWords() {
  		return Sequence(String("[W:"),
  				ZeroOrMore(WSP()).suppressNode(),
  				TexTextIfield(),
  				String("]"))
  			.label(IfieldWords);
  	}
docs: ifield-words ::= %5B.%57.%3A *WSP tex-text-ifield %5D<p>
  <tt>[W:..]</tt>