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I am learning react js. I am a very beginner at this topic. But when I am doing setup to create a react environment I got an error. I have tried to solve the problem by Charles Stover blog in medium. But I got an error Command "up" not found.

Here's my index.js file:

I have been stock on this error on my project when I add "proxy": "http://localhost:6000" in my package.json.

This is the error response after yarn start.

Invalid options object. Dev Server has been initialized using an options object that does not match the API schema.

• options.allowedHosts[0] should be a non-empty string. error Command failed with exit code 1. info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

But everything is fine when I remove the "proxy": "http://localhost:6000".

This is on my package.json:

Edit: This issue is now deprecated since version 3.0.0 of tailwind works with react without having to use CRACO.

While trying to use Tailwind with React in JIT mode the classes that I add have no styles, even after refreshing the page. I have to restart the server for the styles to take effect.

tailwind.config.js:

I have the following repository structure:

cypress folder

• .eslintrc.js
• tsconfig.json
• basic.spec.ts

src folder

.eslintrc.js

tsconfig.base.json

tsconfig.json

My intention is to set the root tsconfig.json only for the src folder, and same goes for .eslintrc.js. Then I try to configure tsconfig.json and .eslintrc.js as well for the cypress folder. But I get the following error when running ESLint:

I'm trying to make a Sign-In page & the Sign-In form has disappeared. It isn't rendering like it should on the DOM anymore. I think it has to do with my import {useState} from 'react'. Everything was working fine until I included the {useState} hook. I am getting the following error message:

react.development.js:1476 Uncaught Error: Invalid hook call. Hooks can only be called inside of the body of a function component.

Im not sure where I went wrong. Any suggestions?

In package.json file react-router-dom dependencies added. App component wrapped by BrowswerRouter , but when I wrap route by switch it says the following error Switch' is not exported from 'react-router-dom'. I deleted the package.json.lock ,node modules, installed npm again and npm install @babel/core --save. Still not working. I successfully wasted 6 hour for this. Can you please help me to fix this? why it's not importing?

Index.js

App.js

I'm currently creating a new React application with create-react-app. After that I install eslint that extends plugin:react/recommended and google. 2 weeks ago I did the same and I had no problems but since 2 days I now get a "Missing "key" prop for element in array" error in my index.tsx and App.tsx files for each html line.

Here is a demo of my problem. This is a new app created from running CRA and only changing the App.js code to this: