LR解析算术表达式

时间:2011-05-28 15:38:34

标签: c# lr

我有LR语法和LR表用于表达式,如(1 + 1),1 +(a + 1)

0:E' - > E

1:E - > E + T

2:E-> Ť

3:T - > T * F

4:T-> ˚F

5:F - >(E)

6:F-> ID

string[,] ActionTable = 
   //+         *       (       )       id   end     E      T       F 
 {   

 {""     ,""     ,"S4"   ,""     ,"S5"   ,""    ,"1"    ,"2"    ,"3"}, // 0
 {"S6"   ,""     ,""     ,""     ,""     ,"AC"  ,""     ,""     ,"" }, // 1
 {"R2"   ,"S7"   ,""     ,"R2"   ,""     ,"R2"  ,""     ,""      ,""},//2                                                              
 {"R4"   ,"R4"   ,""     ,"R4"   ,""     ,"R4"  ,""     ,""     ,""},  // 3                                
 {""     ,""     ,"S4"   ,""     ,"S5"   ,""    ,"8"    ,"2"    ,"3"}, // 4                                
 {"R6"   ,"R6"   ,""     ,"R6"   ,""     ,"R6"  ,""     ,""     ,""},  // 5                               
 {""     ,""     ,"S4"   ,""     ,"S5"   ,""    ,""     ,"9"    ,"3"}, // 6                                
 {""     ,""     ,"S4"   ,""     ,"S5"   ,""    ,""     ,""     ,"10"},// 7                                
 {"S6"   ,""     ,""     ,"S11"  ,""     ,""    ,""     ,""     ,""},  // 8                                
 {"R1"   ,"S7"   ,""     ,"R1"   ,"R1"   ,""    ,""     ,""     ,""},  // 9                                
  {"R3"   ,"R3"   ,""     ,"R3"   ,"R3"   ,""    ,""     ,""     ,""},  //10                                                               
 {"R5"   ,"R5"   ,""     ,"R5"   ,"R5"   ,""    ,""     ,""     ,""}   //11
                        };

我尝试检查表达式,如1 + 1或1+(1 * a)+ 1,但解析器表示此表达式不正确。

我可以用语法修复它吗?

1 个答案:

答案 0 :(得分:1)

您没有数字生产规则。