Why is \'regeneratorRuntime is not defined\' when using async/await with Babel 6, and how can I fix it?

"Babel 6 regeneratorRuntime is not defined"

Question: When using async/await on Babel 6, an error message "regeneratorRuntime is not defined" appears. How can this be fixed?

Answer:

To resolve this issue, Babel must be configured to include the babel-polyfill package, which provides necessary runtime support for async/await.

Step 1: Install Required Packages

npm i -D babel-core babel-polyfill babel-preset-es2015 babel-preset-stage-0 babel-loader

Step 2: Update package.json

"devDependencies": {
  "babel-core": "^6.0.20",
  "babel-polyfill": "^6.0.16",
  "babel-preset-es2015": "^6.0.15",
  "babel-preset-stage-0": "^6.0.15"
}

Step 3: Configure Babel (in .babelrc)

{
  "presets": [ "es2015", "stage-0" ]
}

Step 4: Activate Polyfill

In your startup file:

require("babel-core/register");
require("babel-polyfill");

For Webpack Users:

Place as the first value of the entry array in the webpack configuration:

module.exports = {
  entry: ['babel-polyfill', './test.js'],
  ...
}

For Testers:

Run tests with Babel:

mocha --compilers js:babel-core/register --require babel-polyfill

By completing these steps, Babel will include the necessary runtime support for async/await, eliminating the "regeneratorRuntime is not defined" error.

The above is the detailed content of Why is \'regeneratorRuntime is not defined\' when using async/await with Babel 6, and how can I fix it?. For more information, please follow other related articles on the PHP Chinese website!