babel-helpers

What is babel-helpers?

The babel-helpers npm package provides a collection of helper functions used by Babel to perform various transformations and polyfills. These helpers are used internally by Babel to handle common tasks such as class inheritance, object spread, and async/await transformations.

What are babel-helpers's main functionalities?

Class Inheritance

The `inherits` helper is used to set up prototype inheritance between two constructor functions. This is useful when you need to create a subclass that inherits from a parent class.

const inherits = require('babel-helpers').inherits;

function Parent() {}
function Child() {
  Parent.call(this);
}
inherits(Child, Parent);

Object Spread

The `objectSpread` helper is used to merge properties from multiple objects into a single object. This is similar to the object spread operator `{...obj}` in JavaScript.

const objectSpread = require('babel-helpers').objectSpread;

const obj1 = { a: 1, b: 2 };
const obj2 = { b: 3, c: 4 };
const result = objectSpread({}, obj1, obj2);
console.log(result); // { a: 1, b: 3, c: 4 }

Async/Await

The `asyncToGenerator` helper is used to transform an async function into a generator function. This is useful for environments that do not natively support async/await syntax.

const asyncToGenerator = require('babel-helpers').asyncToGenerator;

const asyncFunction = asyncToGenerator(function* () {
  const result = yield fetch('https://api.example.com/data');
  return result.json();
});

asyncFunction().then(data => console.log(data));

Other packages similar to babel-helpers

core-js

Core-js is a modular standard library for JavaScript that includes polyfills for ECMAScript features. It provides similar functionality to babel-helpers by offering polyfills for modern JavaScript features, but it is more comprehensive and includes a wider range of polyfills.

lodash

Lodash is a utility library that provides a wide range of functions for common programming tasks, such as manipulating arrays and objects. While it is not specifically focused on Babel transformations, it offers similar helper functions that can be used to achieve similar results.

tslib

Tslib is a runtime library for TypeScript that provides helper functions for various TypeScript features, such as class inheritance and async/await. It is similar to babel-helpers in that it provides runtime support for language features, but it is specifically designed for TypeScript.

README

babel-helpers

Collection of helper functions used by Babel transforms.

Install

npm install --save-dev babel-helpers

Usage

import * as helpers from 'babel-helpers';
import * as t from 'babel-types';

const typeofHelper = helpers.get('typeof');

t.isExpressionStatement(typeofHelper);
// true