README.md

    npm version install size code coverage backers sponsors license dependency status Join the chat at https://is.gd/rollup_chat

    Rollup

    Overview

    Rollup is a module bundler for JavaScript which compiles small pieces of code into something larger and more complex, such as a library or application. It uses the standardized ES module format for code, instead of previous idiosyncratic solutions such as CommonJS and AMD. ES modules let you freely and seamlessly combine the most useful individual functions from your favorite libraries. Rollup can optimize ES modules for faster native loading in modern browsers, or output a legacy module format allowing ES module workflows today.

    Quick Start Guide

    Install with npm install --global rollup. Rollup can be used either through a command line interface with an optional configuration file, or else through its JavaScript API. Run rollup --help to see the available options and parameters. The starter project templates, rollup-starter-lib and rollup-starter-app, demonstrate common configuration options, and more detailed instructions are available throughout the user guide.

    Commands

    These commands assume the entry point to your application is named main.js, and that you'd like all imports compiled into a single file named bundle.js.

    For browsers:

    # compile to a <script> containing a self-executing function
    rollup main.js --format iife --name "myBundle" --file bundle.js

    For Node.js:

    # compile to a CommonJS module
    rollup main.js --format cjs --file bundle.js

    For both browsers and Node.js:

    # UMD format requires a bundle name
    rollup main.js --format umd --name "myBundle" --file bundle.js

    Why

    Developing software is usually easier if you break your project into smaller separate pieces, since that often removes unexpected interactions and dramatically reduces the complexity of the problems you'll need to solve, and simply writing smaller projects in the first place isn't necessarily the answer. Unfortunately, JavaScript has not historically included this capability as a core feature in the language.

    This finally changed with ES modules support in JavaScript, which provides a syntax for importing and exporting functions and data so they can be shared between separate scripts. Most browsers and Node.js support ES modules. However, Node.js releases before 12.17 support ES modules only behind the --experimental-modules flag, and older browsers like Internet Explorer do not support ES modules at all. Rollup allows you to write your code using ES modules, and run your application even in environments that do not support ES modules natively. For environments that support them, Rollup can output optimized ES modules; for environments that don't, Rollup can compile your code to other formats such as CommonJS modules, AMD modules, and IIFE-style scripts. This means that you get to write future-proof code, and you also get the tremendous benefits of...

    Tree Shaking

    In addition to enabling the use of ES modules, Rollup also statically analyzes and optimizes the code you are importing, and will exclude anything that isn't actually used. This allows you to build on top of existing tools and modules without adding extra dependencies or bloating the size of your project.

    For example, with CommonJS, the entire tool or library must be imported.

    // import the entire utils object with CommonJS
    var utils = require('utils');
    var query = 'Rollup';
    // use the ajax method of the utils object
    utils.ajax('https://api.example.com?search=' + query).then(handleResponse);

    But with ES modules, instead of importing the whole utils object, we can just import the one ajax function we need:

    // import the ajax function with an ES import statement
    import { ajax } from 'utils';
    var query = 'Rollup';
    // call the ajax function
    ajax('https://api.example.com?search=' + query).then(handleResponse);

    Because Rollup includes the bare minimum, it results in lighter, faster, and less complicated libraries and applications. Since this approach is based on explicit import and export statements, it is vastly more effective than simply running an automated minifier to detect unused variables in the compiled output code.

    Compatibility

    Importing CommonJS

    Rollup can import existing CommonJS modules through a plugin.

    Publishing ES Modules

    To make sure your ES modules are immediately usable by tools that work with CommonJS such as Node.js and webpack, you can use Rollup to compile to UMD or CommonJS format, and then point to that compiled version with the main property in your package.json file. If your package.json file also has a module field, ES-module-aware tools like Rollup and webpack will import the ES module version directly.

    Contributors

    This project exists thanks to all the people who contribute. [Contribute].

    Backers

    Thank you to all our backers! 🙏 [Become a backer]

    Sponsors

    Support this project by becoming a sponsor. Your logo will show up here with a link to your website. [Become a sponsor]

    License

    MIT

    项目简介

    🚀 Github 镜像仓库 🚀

    源项目地址

    https://github.com/rollup/rollup

    发行版本 138

    v2.58.0

    全部发行版

    贡献者 192

    全部贡献者

    开发语言

    • JavaScript 81.4 %
    • TypeScript 18.4 %
    • HTML 0.2 %
    • CSS 0.0 %
    • Shell 0.0 %