How to use babel-runtime in Babel 6?

Using Babel Runtime in Babel 6 primarily enables the reuse of Babel-injected helper functions within compiled code, minimizes redundancy in generated output, and supports code transformations during the build process, such as async/await. The following are the steps to implement Babel Runtime:

1. Install the necessary packages

First, install babel-core and babel-runtime, along with the babel-plugin-transform-runtime plugin. This can be achieved using npm:

bash
npm install --save-dev babel-core
npm install --save babel-runtime
npm install --save-dev babel-plugin-transform-runtime

2. Configure .babelrc file

Next, create a .babelrc file in the project root (if it doesn't already exist) and add the transform-runtime plugin to your Babel configuration. This plugin automatically imports modules from babel-runtime to facilitate their use in compiled code. The configuration would appear as follows:

json
{
  "plugins": [
    ["transform-runtime", {
      "helpers": true,
      "polyfill": true,
      "regenerator": true
    }]
  ]
}

The meaning of these configuration options is as follows:

• helpers: Set to true to enable automatic import of Babel helper functions.
• polyfill: Set to true to import a global polyfill that emulates a complete ES2015+ environment.
• regenerator: When enabled, supports generators and async/await.

3. Write ES2015+ code

Now you can start writing JavaScript code using ES2015 or higher syntax, such as arrow functions, Promises, and async/await.

javascript
async function fetchData() {
  const response = await fetch('https://api.example.com/data');
  const data = await response.json();
  return data;
}

4. Build process

During the build process (e.g., using Webpack or Babel CLI), Babel will automatically apply the transform-runtime plugin to convert your code into backward-compatible JavaScript, reducing global namespace pollution and eliminating code duplication.

5. Run and test

Finally, run your application or perform tests to verify functionality. With polyfills and runtime support included, applications written in modern JavaScript should operate correctly even in older browser environments.

This configuration is particularly beneficial for library and tool development, as it prevents global namespace pollution and ensures libraries do not conflict due to duplicate helper functions.