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Questions tagged [babeljs]

Babel (formerly 6to5) is a JavaScript compiler. It transforms ES6+/ES2015 code into ES5 code.

Babel (formerly 6to5) is a JavaScript compiler.
It transforms ES6+/ES2015 code into ES5 code.

Important Note about Babel v6

With Babel v6, Babel became a platform for JS code transformations. That means it doesn't include any ES2015 to ES5 transformers by default. This has to be enabled explicitly.

Please see

Resources:

9692 questions
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Syntax error - Support for the experimental syntax 'decorators-legacy' isn't currently enabled

I'm trying to build JS react project with decorators. My .babelrc looks like this: { "presets": [ "@babel/preset-env", "@babel/preset-react", ], "plugins": [ "@babel/plugin-transform-runtime", …
olga_babic
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Dynamically add child components in React

My goal is to add components dynamically on a page/parent component. I started with some basic example template like this: main.js: var App = require('./App.js'); var SampleComponent = require('./SampleComponent.js'); ReactDOM.render(,…
Justin Trevein
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Cannot find module '@babel/core'

I am following along with this webpack4/react tutorial: https://www.youtube.com/watch?v=deyxI-6C2u4 I have followed it exactly up until the part where he runs npm start. The difference is, his app runs, and mine gets the error: Cannot find module…
J. Doe
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10 answers

Babel file is copied without being transformed

I have this code: "use strict"; import browserSync from "browser-sync"; import httpProxy from "http-proxy"; let proxy = httpProxy.createProxyServer({}); and I have installed babel-core and babel-cli globally via npm. The point is when I try to…
Raul Vallespin
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Babel 7 - ReferenceError: regeneratorRuntime is not defined

I have an application that is a node backend and a react frontend. I get the following error when i try to build/run my node application. Node: v10.13.0 Error: dist/index.js:314 regeneratorRuntime.mark(function _callee(productId) { …
Kay
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3 answers

ES6 `export * from import`?

Is there a syntax using ES6 or ES7 or babel which will allow me to easily bundle together many groups of sub files? E.g., given: ./action_creators/index.js ./action_creators/foo_actions.js ./action_creators/bar_actions.js Have index.js import foo…
Jordan Warbelow-Feldstein
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5 answers

Webpack babel 6 ES6 decorators

I've got a project written in ES6 with webpack as my bundler. Most of the transpiling works fine, but when I try to include decorators anywhere, I get this error: Decorators are not supported yet in 6.x pending proposal update. I've looked over…
Pavlin
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Can't require() default export value in Babel 6.x

In Babel 5.x, I can write the following code: app.js export default function (){} index.js require('babel/register'); require('./app')(); Then, I can run node index.js with no errors. However, using Babel 6.x, running the following…
XGHeaven
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babel CLI copy nonjs files

I'm running a babel cli command babel src --out-dir lib To copy the es6 scripts from src into lib. However, it wont copy css/scss files I have in the src/ folder. Is there a way to make it copy them as well?
yangli-io
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`regeneratorRuntime` is not defined when running Jest test

The title pretty much explains what I'm facing. I'm trying to test a React component that has some state, and I attempt to provide my store to the component in order to get what it needs. When I run the test of the component using Jest, I get the…
rafafan2010
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Babel unexpected token import when running mocha tests

The solutions offered in other related questions, such as including the proper presets (es2015) in .babelrc, are already implemented in my project. I have two projects (lets call them A and B) which both use ES6 module syntax. In Project A, I'm…
ThinkingInBits
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'import' and 'export' may only appear at the top level

I'm using webpack with vuejs. Webpack does its thing, but when I look at the outputted app.js file, it gives me this error. 'import' and 'export' may only appear at the top level I'm assuming it's a problem with babel not converting the code?…
Jayson H
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Error: Missing class properties transform

Error: Missing class properties transform Test.js: export class Test extends Component { constructor (props) { super(props) } static contextTypes = { router: React.PropTypes.object.isRequired } .babelrc: { "presets": ["es2015",…
speak
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UglifyJS throws unexpected token: keyword (const) with node_modules

A small project I started make use a node module (installed via npm) that declares const variables. Running and testing this project is well, but browserify fails when UglifyJS is executed. Unexpected token: keyword (const) Here is a generic Gulp…
Yanick Rochon
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Webpack import returns undefined, depending on the order of imports

I'm using webpack + babel. I have three modules looking like this: // A.js // some other imports here console.log('A'); export default 'some-const'; // B.js import someConst from './A'; console.log('B', someConst); export default…
Alec Mev
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