vn.contextStack2.size = size;
		public boolean evalBoolean(VTDNav vn){			boolean a = false;			vn.push2();			// record stack size			int size = vn.contextStack2.size;		        try{					a = (evalNodeSet(vn) != -1);			vn.contextStack2.size = size;			}catch (Exception e){			}			//rewind stack			reset(vn);			vn.pop2();			return a;		}