Explore over 1 million open source packages. This library is required to support the ES6 generator functions that are used to implement async/await functionality. Async and await syntax in JavaScript relies on asynchronous generator functions, and without the regenerator-runtime library, your code will throw the "ReferenceError: regeneratorRuntime is not defined" error. In other words, when you use async/await functions, your code is transformed by the Babel transpiler to use generator functions, which are implemented using the regenerator-runtime library. .babel, react hookasync awaitUncaught ReferenceError: regeneratorRuntime is not defined let electron = require('electron'); // electron If you're using babel 7, the package has been renamed to @babel/plugin-transform-runtime . Besides polyfill, I use babel-plugin-transform-r Have a question about this project? WebSearch for jobs related to Uncaught referenceerror base64 is not defined in magento 2 or hire on the world's largest freelancing marketplace with 22m+ jobs. Is there a way to get version from package.json in nodejs code? Step 1: Install the Regenerator-runtime Library Step 2: Import the Regenerator You have to add a version thats recent enough to support async/await, so Babel does not try to add a polyfill. I'm use @babel/plugin-transform-runtime, still got this issue. How to Fix the ReferenceError: RegeneratorRuntime is Not Defined Error? How do I fix the "ReferenceError: regeneratorRuntime is not defined" error in my code? 1) "useBuiltIns": "entry" does not load polyfills for all features, it actually removes those not needed according to the docs 2) It is recommended to use .browserlistrc (or other browserlist config options), since many other tools than just babel use those. Update : The Babel 7 post also has a more in-depth answer. Babel 7.4.0 or later (core-js 2 / 3) As of Babel 7.4.0 , @babel/polyfill is deprecat This error indicates that the regenerator-runtime library is not installed or imported in the code, and it needs to be installed and imported to resolve the error. The runtime optional transformer does three things: I have no experience with this, but I suspect you would do so by including the optional: ['runtime'] option from the Babel docs in your babelPreprocessor config, viz. BabelJavaScriptsyntaxAPIIteratorGeneratorSetMapsProxyReflectSymbolPromiseObject.assign, babel-polyfill ES6 API API, npm install --save-dev babel-plugin-transform-runtime, https://blog.csdn.net/qq_40028324/article/details/81235290 , referenceerror: activexobject is not defined. Babel and regenerator-runtime are often used together to write and run code that uses async and await syntax. Well occasionally send you account related emails. Here is a code example that demonstrates how to resolve the "ReferenceError: regeneratorRuntime is not defined" error. This snippet must be put in .babelrc.js file (or just .babelrc if you use json). You can install Babel and its plugins using npm and configure it to transpile your code. If like myself, you had the same error message: ReferenceError: regeneratorRuntime is not defined but were running Babel within a NodeJS environment, then simply doing the following will likely solve your problem: Then insert the following require statement towards the top of the affected module to obtain required (generator) behaviour: This should be all you need, just importing the module adds required polyfill behaviour at runtime. My simple solution: npm install --save-dev babel-plugin-transform-runtime babel-polyfill regenerator-runtime Jest @Magnuti Babel 6 has been deprecated and not maintained actively. Webactivexobject is not definedCSDNVBA Word.Application user-defined type not defined Just add: