module.exports = {
  presets: ["@vue/cli-plugin-babel/preset"],
  plugins: ["@babel/plugin-proposal-optional-chaining"],
  compact: false,
  plugins:[
    // null判断运算符支持 ??
    // '@babel/plugin-proposal-nullish-coalescing-operator',
    // 链判断运算符支持 ?.
    '@babel/plugin-proposal-optional-chaining'
]
};