Question

当尝试返回在对象中找到的包含：host的子代数量时，该函数始终返回undefined。

const plugin = stylelint.createPlugin(ruleName, isEnabled => {
  let childrenFound = 0;
  childrenFound = lookForChildren(rule.nodes, childrenFound);
  console.log(childrenFound); // Wrong Value: Always undefined
}


let lookForChildren = function(nodes, childFound) {

  if(childFound > 1) {

    console.log(childFound);

    return childFound;

  }

  nodes.forEach(node => {

    if (node.selector != undefined) {

      const selector = node.selector.replace(":host-context", "");

      if (selector.includes(":host")) {

        childFound++;

        return lookForChildren(node.nodes, childFound);

      } else {

        return lookForChildren(node.nodes, childFound);

      }

    }

  });
// This returns the wrong value so i deleted it
return childFound;
};

但是它应该返回childFound变量，该变量仅在大于1时才返回。

此功能检查scss文档是否包含一个选择器，该选择器具有多个:host选择器，因为浏览器对它的编译与预期不同。

childFound大于1时：

预期：return childFound // Childfound is 2 or higher

实际：childrenFound始终未定义。

Answer 1

使用for...to解决了我的问题。感谢@HarunYilmaz指出这一点，并感谢大家为我提供帮助。

Answer 2

您应该在函数内部返回值，而不是在该函数之外或之下，只需更改return语句在最后一个花括号内的位置即可。检查以下代码：

const plugin = stylelint.createPlugin(ruleName, isEnabled => {
  let childrenFound = 0;
  childrenFound = lookForChildren(rule.nodes, childrenFound);
  console.log(childrenFound); // Wrong Value: Always undefined
}


let lookForChildren = function(nodes, childFound) {

  if(childFound > 1) {

    console.log(childFound);

    return childFound;

  }

  nodes.forEach(node => {

    if (node.selector != undefined) {

      const selector = node.selector.replace(":host-context", "");

      if (selector.includes(":host")) {

        childFound++;

        return lookForChildren(node.nodes, childFound);

      } else {

        return lookForChildren(node.nodes, childFound);

      }

    }

  });
return childFound;
};

// This returns the wrong value so i deleted it

递归函数始终在末尾返回undefined。怎么修？

2 个答案: