node.js - "format cjs"; 这句话是什么意思

Question

我 npm publish 出去的文件头部 都有这个字符串
但是我下面是用

export default 定义的 import别的文件失败

把 format cjs 去掉 就可以import

Answer 1

should be the abbreviation of format commonjs.
probably means that npm module should organize modules according to Commonjs, so using ES6 modules will result in undefined

I don’t understand what the question is saying

But I defined it below using
export default and failed to import other files

What does it mean