{
  "presets": [
    ["env", {
      "modules": false,
      "targets": {
        "browsers": ["> 1%", "last 2 versions", "not ie <= 8"]
      }
    }],
    "stage-2"
  ],

    //按需加载
  "plugins": [["import", {
    "libraryName": "iview",
    "libraryDirectory": "src/components"
  }]]
}