此yacc语法有什么问题？

Question

我有一个yacc解析器，可以在其中解析“ abc = 123”（VAR = VAR），abc = [1 2 3]（VAR = value_series / string）和abc = [[123]]等命令。

我需要解析abc = [xyz = [1 2 3] jkl = [3 4 5]]。由于规则2之间的歧义，此语法失败了（我想，它无法区分value_series和新规则。

我尝试了一个案例：VAR_NAME等价quote_or_brace模型等价quote_or_brace value_series quote_or_brace净等价quote_or_brace value_series quote_or_brace quote_or_brace

没用

series:
   | PLUS series
   {
   }
   | series VAR_NAME EQUAL VAR_NAME
   {
     delete [] $2;
     delete [] $4;
   }
   | series VAR_NAME EQUAL quote_or_brace value_series quote_or_brace
   {
     delete [] $2;
   }
   | series VAR_NAME EQUAL quote_or_brace quote_or_brace value_series quote_or_brace quote_or_brace
   {
     delete [] $2;
   }
   | error
   {
     setErrorMsg(string("error"));
     YYABORT;
   };

Answer 1

如果是我，我可能会写一套类似于以下的规则：

assignment_list
  : assignment
  | assignment assignment_list
  ;

assignment
  : VAR_NAME '=' assignment_rhs
  ;

assignment_rhs
  : expression
  | '[' opt_expression_list ']'  /* allows var1 = [ ... ] */
  ;

opt_expression_list
  : /* empty */
  | expression_list
  ;

expression_list
  : expression
  | expression expression_list
  ;

expression
  : VAR_NAME   /* a variable name, as in var1 = var2 */
  | NUMBER     /* some kind of number, as in var1 = 123 */
  | STRING     /* quoted string, as in var1 = "foo" */
  | assignment /* allows nesting of assignments, as in var1 = [var2 = 4] */
               /* also allows things like var1 = var2 = 123 */
  ;

请注意，无论如何都不会对此进行测试，并且我不确定从expression到assigment的递归。