buble

What is buble?

Bublé is a JavaScript compiler that takes your ES2015+ code and turns it into code that can run in older browsers. It is designed to be fast and to produce compact output.

What are buble's main functionalities?

Transpiling ES6 to ES5

Bublé can transpile modern ES6+ syntax to ES5, making it compatible with older browsers. This example shows how an arrow function is transformed into a regular function.

const buble = require('buble');
const result = buble.transform(`const add = (a, b) => a + b;`);
console.log(result.code); // 'var add = function (a, b) { return a + b; };'

Source Maps

Bublé can generate source maps, which are useful for debugging. This example shows how to generate a source map for the transformed code.

const buble = require('buble');
const result = buble.transform(`const add = (a, b) => a + b;`, { source: 'input.js', file: 'output.js' });
console.log(result.map);

Custom Transforms

Bublé allows you to customize which transformations to apply. This example shows how to disable the transformation of ES6 classes.

const buble = require('buble');
const result = buble.transform(`class Person { constructor(name) { this.name = name; } }`, { transforms: { classes: false } });
console.log(result.code);

Other packages similar to buble

babel

Babel is a widely-used JavaScript compiler that supports a wide range of plugins and presets for transforming ES6+ code to ES5. It is more feature-rich and extensible compared to Bublé, but it can be slower and produce larger output.

typescript

TypeScript is a superset of JavaScript that adds static types. It also includes a compiler that can transpile TypeScript (and modern JavaScript) to ES5. While it offers more features like type checking, it is more complex to set up and use compared to Bublé.

esbuild

esbuild is an extremely fast JavaScript bundler and minifier. It can also transpile modern JavaScript to older versions. It is known for its speed and efficiency, but it is less configurable than Babel.

README

Maintenance status

Bublé was created when ES2015 was still the future. Nowadays, all modern browsers support all of ES2015 and (in some cases) beyond. Unless you need to support IE11, you probably don't need to use Bublé to convert your code to ES5.

Since IE11 is an unfortunate reality for some people, we will continue to release bugfixes, but new features won't be added unless in exceptional circumstances.

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Bublé

The blazing fast, batteries-included ES2015 compiler

• Try it out at buble.surge.sh
• Read the docs at buble.surge.sh/guide

Quickstart

Via the command line...

npm install -g buble
buble input.js > output.js

...or via the JavaScript API:

var buble = require( 'buble' );
var result = buble.transform( source ); // { code: ..., map: ... }

License

MIT

Changelog

0.20.0 (2020-03-26)

• This is the last Buble version to work on Node v4 & v6. Going forward, support for old Node versions that reached End-of-Life will not be actively maintained. #250
• Fix recognition of catch-declared variables (#237)
• Prevent labels from being renamed due to let/const transpilation. (#236)
• Fix scoping of variables declared in for loops. (#233)
• Fix an error when transpiling for (a[0] in b). (#232)
• Fix an error when transpiling for with an empty init. (#226)
• Fix let/const transpilation when combined with shorthand properties. (#229)
• Fix JSX not respecting advanced white space characters. (#218)
• Fix name collision when transpiling A = class extends A {}. (#209)
• Fix os-homedir dependency warnings on install. (#207)
• Upgrade dependencies to their latest patch versions, fixing security audit warnings. (#250)