Babel 7 - 未捕获的 ReferenceError：未定义 regeneratorRuntime

Question

I'm getting the error Uncaught ReferenceError: regeneratorRuntime is not defined using React with webpack and Babel .

I've followed this answer by defining my .babel.rc as:

{
  "presets": ["@babel/preset-env", "@babel/preset-react"] ,
  "plugins": [
      ["@babel/plugin-transform-runtime"]
  ]
}

and running:

npm i --save-dev @babel/plugin-transform-runtime

However, I get the exact same error afterwards. I've also followed this other answer and this one , but still get the exact same error.

My babel specific installations in package.json are as follows:

  "dependencies": {
    "@babel/runtime": "^7.14.6"
  },
  "devDependencies": {
    "@babel/core": "^7.14.6",
    "@babel/plugin-transform-runtime": "^7.14.5",
    "@babel/preset-env": "^7.14.7",
    "@babel/preset-react": "^7.14.5"
  }

Any ideas?

Answer 1

This ended up working for me:

How to allow async functions in React + Babel?

My problem was that I was defining the babel plugin in both my .babel.rc file and my webpack.config.js file. I needed to remove that plugin from my webpack.config.js and simply use it only in my .babel.rc file. Then it worked well.

Answer 2

{ "presets": [ [ "@babel/preset-env", { "targets": { "node": "9.2.1" } } ], "@babel/preset-react" ] }

This is my file .babelrc

Look:

@babel/preset-env is a smart preset that allows you to use the latest JavaScript without needing to micromanage which syntax transforms (and optionally, browser polyfills ) are needed by your target environment(s). This both makes your life easier and JavaScript bundles smaller!

your problemes:

You are using "@ babel / preset-env" you must specify the version of node to compile. "node> 7.6". I recommend 10.

Why node > 7.6 Node.js 7.6 has shipped with official support for async/await enabled by default and better performance on low-memory devices.

How do you specify the version: It's simple

targets.node string | "current".

If you want to compile against the current node version, you can specify "node": "current", which would be the same as "node": process.versions.node.

AND FOR ME LOOK LIKE THIS:

{
  "presets": [
    [
      "@babel/preset-env",
      {
        "targets": {
          "node": "9.2.1"
        }
      }
    ],
    "@babel/preset-react"
  ]
}

This allows the compiler to understand ASYNC AWAIT, hope it helps you!

Answer 3

hey I ran into the same problem and I am using Babel 7, for me I installed these two dependencies:

npm install --save @babel/runtime
npm install --save-dev @babel/plugin-transform-runtime

And, in .babelrc, add:

{
"presets": ["@babel/preset-env"],
"plugins": [
    ["@babel/transform-runtime"]
]

}

and this solved my problem