// 新建.babelrc
{
  "presets": [
    ["es2015", {"modules": false}],
       // webpack现在已经支持原生的import语句了, 并且将其运用在tree-shaking特性上
    "stage-2",
      // 规定JS运用的语言规范层级
      // Stage 2 是 "草案", 4 是 "已完成", 0 is "稻草人(strawman)"。
      // 详情查看 https://tc39.github.io/process-document/
    "react"
      // 转译React组件为JS代码
  ],
  "plugins": [
    "transform-runtime",
    // "react-hot-loader/babel",
    "transform-object-rest-spread",
    ["transform-react-jsx", {
      "pragma": "React.createElement" // 默认 pragma 为 React.createElement
    }],
    "external-helpers",
    "transform-flow-strip-types",
    "syntax-flow",
    "transform-es2015-modules-commonjs"
      // 开启react代码的模块热替换（HMR）
  ]
}