{lexical items}
symbol = (word, numeral, empty{ () }, nilsy, charliteral, truesy, falsesy,
          open, close, sqopen, sqclose, curlopen, curlclose,
          letsy, recsy, insy, comma, colon,
          ifsy, thensy, elsesy, lambdasy, dot,
          quote,
          conssy,
          orsy, andsy,
          eq, ne, lt, le, gt, ge,
          plus, minus, times, over,
          nullsy, hdsy, tlsy, notsy,
          eofsy
         );

{\fB Lexical Types. \fP}