@babel/plugin-syntax-nullish-coalescing-operator

What is @babel/plugin-syntax-nullish-coalescing-operator?

The @babel/plugin-syntax-nullish-coalescing-operator package allows Babel to parse code that uses the nullish coalescing operator (??). This operator is a logical operator that returns its right-hand side operand when its left-hand side operand is null or undefined, and otherwise returns its left-hand side operand. This package does not transform the nullish coalescing syntax; it only enables Babel to understand it.

What are @babel/plugin-syntax-nullish-coalescing-operator's main functionalities?

Parsing nullish coalescing operator

This code demonstrates how the nullish coalescing operator is used to provide a default value ('default string') in case the left-hand operand (foo) is null or undefined.

const foo = null ?? 'default string';

Other packages similar to @babel/plugin-syntax-nullish-coalescing-operator

@babel/plugin-proposal-nullish-coalescing-operator

This package not only allows Babel to parse the nullish coalescing operator but also transforms it. This means it can convert code using the nullish coalescing operator into equivalent code that does not use the operator, allowing it to run in environments that do not support the operator natively. It offers a superset of the functionality provided by @babel/plugin-syntax-nullish-coalescing-operator.

@babel/preset-env

While not exclusively focused on the nullish coalescing operator, @babel/preset-env includes support for it among many other JavaScript features. This preset automatically determines the Babel plugins and polyfills needed based on the target environment's support for JavaScript features. It's a more comprehensive solution for writing modern JavaScript that is compatible with older environments.

README

@babel/plugin-syntax-nullish-coalescing-operator

Allow parsing of the nullish-coalescing operator.

Installation

npm install --save-dev @babel/plugin-syntax-nullish-coalescing-operator

Usage

Via .babelrc (Recommended)

.babelrc

{
  "plugins": ["@babel/plugin-syntax-nullish-coalescing-operator"]
}

Via CLI

babel --plugins @babel/plugin-syntax-nullish-coalescing-operator script.js

Via Node API

require("@babel/core").transform("code", {
  plugins: ["@babel/plugin-syntax-nullish-coalescing-operator"]
});