Question

我需要解析像对象{"f": 1, "i": 2, "g": 5, ...}这样的JSON，但与常规JSON对象不同，输入可以在对象中出现零次或一次......

所以，这是错误的对象{"f": 1, "f": 1, "i": 2, ...}，因为它有两次＆＃34; f两次＆＃34;。

并且，这个对象很好{"i": 2}，因为它只有关键字＆＃34; i＆＃34;并且它不会发生多次。

这是我尝试过的。我知道它不起作用，但我不知道如何将它设置为正确。

RuleMemberList
    : RuleMember
        {{$$ = {}; $$[$1[0]] = $1[1];}}
    | RuleMemberList ',' RuleMember
        {$$ = $1; $1[$3[0]] = $3[1];}
    ;

RuleMember
    : I ':' RuleString
          {$$ = [$1, $3];}
    | G ':' RuleString
          {$$ = [$1, $3];}
    | F ':' RuleFinder
          {$$ = [$1, $3];}
    | A ':' RuleAction
          {$$ = [$1, $3];}
    | T ':' RuleTarget
          {$$ = [$1, $3];}
    | P ':' RuleNumber
          {$$ = [$1, $3];}
    | C ':' RuleChance
          {$$ = [$1, $3];}
    | L ':' RuleLayers
          {$$ = [$1, $3];}
    | R ':' RuleString
          {$$ = [$1, $3];}
    | E ':' RuleEvents
          {$$ = [$1, $3];}
    | B ':' RuleBinds
          {$$ = [$1, $3];}
    ;

我能以某种方式将其定义为零或一次出现吗？

Answer 1

向地图添加元素时检查重复项。类似的东西：

| RuleMemberList ',' RuleMember
    { $$ = $1;
      if ($3[0] in $1)
        error("duplicate key ", $3[0], " in map");
      else
        $1[$3[0]] = $3[1];}
;

Bison在语法文件中出现零次或一次出现

1 个答案: