Examples ...
begin i:=j; j:=7 end. /* input */ binop 79460 OP := link 0 operands 79412 79412 ID I link 79508 79508 ID J link 0 binop 79652 OP := link 0 operands 79604 79604 ID J link 79700 79700 NUM 7 link 0 cons 79652 OP := link 0 operands 79604 0 NULL cons 79460 OP := link 79652 operands 79412 79652 OP := link 0 operands 79604 makeprogn 79364 OP progn link 0 operands 79460 79460 OP := link 79652 operands 79412 yyparse result = 0 79364 OP progn link 0 operands 79460 (progn (:= I J) (:= J 7))