依赖介绍 参考： : " devDependencies " : { " babel-core " : " ^6.26.3 " , " babel-plugin-transform-react-jsx " : " ^6.24.1 " , " babel-preset-env " : " ^1.7.0 " , " parcel-bundler " : " ^1.12.4 " } 1.捆绑包 为打包，很快 2.babel-preset-env不再需要添加20