Jison：二进制操作语法冲突

Question

在试图建立我的Jison语法我有：

%left 'OR' 'AND' 

%% 

Expression: 
    Operation 
; 

Operation: 
    Expression Operator Expression {$$ = new yy.LogicalExpression($2, $1, $3)} 
; 

Operator: 
    'AND' 
| 'OR' 
; 

但是，这导致以下冲突的消息：

Conflict in grammar: multiple actions possible when lookahead token is OR in state 6 
- reduce by rule: Operation -> Expression Operator Expression 
- shift token (then go to state 5) 
Conflict in grammar: multiple actions possible when lookahead token is AND in state 6 
- reduce by rule: Operation -> Expression Operator Expression 
- shift token (then go to state 4) 

States with conflicts: 
State 6 
    Operation -> Expression Operator Expression . #lookaheads= $end OR AND 
    Operation -> Expression .Operator Expression 
    Operator -> .AND 
    Operator -> .OR 

当我更换消除Operator非而不是直接写出表达模式：

%left 'OR' 'AND' 

%% 

Expression: 
    Operation 
; 


Operation: 
    Expression 'AND' Expression {$$ = new yy.LogicalExpression($2, $1, $3)} 
| Expression 'OR' Expression {$$ = new yy.LogicalExpression($2, $1, $3)} 
; 

我没有这样的错误或者，为什么第一个语法有冲突，但不是第二个？他们似乎相当于我的理解。

提前致谢！

Answer 1

预测太多，但第一种形式无论如何都是错误的。第二种形式是正确的。您需要为AND和OR以及所有其他操作员编写单独的作品。否则，您无法获得运算符优先级。