Couldn't find a declaration file for module 'react'

[JJ810]

Describe the bug

I created a typescript template create-react-app by running npx create-react-app --template typescript and tried to import
useEffect and useState. After I import and save file, I got an error: Could not find a declaration file for module 'react'

Did you try recovering your dependencies?

6.14.6

Environment

current version of create-react-app: 4.0.0
running from /Users/healer/.npm/_npx/25783/lib/node_modules/create-react-app

System:
OS: macOS High Sierra 10.13.6
CPU: (6) x64 Intel(R) Core(TM) i5-8400 CPU @ 2.80GHz
Binaries:
Node: 10.22.1 - ~/.nvm/versions/node/v10.22.1/bin/node
Yarn: 1.22.4 - /usr/local/bin/yarn
npm: 6.14.6 - ~/.nvm/versions/node/v10.22.1/bin/npm
Browsers:
Chrome: 86.0.4240.111
Edge: 86.0.622.51
Firefox: 81.0.2
Safari: 13.0.5
npmPackages:
react: ^17.0.1 => 17.0.1
react-dom: ^17.0.1 => 17.0.1
react-scripts: 4.0.0 => 4.0.0
npmGlobalPackages:
create-react-app: Not Found

Steps to reproduce

1. run npx create-react-app --template typescript
2. open App.tsx and import useEffect and/or useState import React, { useEffect, useState } from 'react'
3. save file and refresh

Actual behavior

I got error and couldn't run the project.

[ehsankhfr]

This is already discussed in #9882

[BrandonGardner2]

This is already discussed in #9882
@ehsankhfr

I don't think that issue is discussing the same problem. This appears to be in reference to the type declaration files, not React itself. I have the same error on a fresh CRA Typescript project today and the issue you reference already had a fix merged.

I was able to resolve this by removing node_modules and reinstalling.

[JJ810]

@BrandonGardner2, you should run

npm install @types/react

to fix this issue. But I couldn't find where to add this package in this repo.

[BrandonGardner2]

@BrandonGardner2, you should run

npm install @types/react

to fix this issue. But I couldn't find where to add this package in this repo.

yea, it looked as if the @types/react failed to install in the initial creation. The dependency is created in the package.json. I just wiped node_modules in case anything else was missed.

luckily that is all that was needed haha.

[shyaboi]

@BrandonGardner2, you should run

npm install @types/react

to fix this issue. But I couldn't find where to add this package in this repo.

This worked for me, and i used the create-react-app tsx starter template.

[jowanwondergemincentro]

Why does this work with everyone, iand not me.
I am already struggling with this for a long time.
Even after copy pasting the entire folder 'react-native-barcode-scanner-google' in the @types folder, it keeps throwing the same error. I also tried to add this line, to the tsconfig.json "noImplicitAny": false".

All without any success. Any suggestion would be greatly appreciated

[LudwigThePig]

I ran npx create-react-app my-app --template typescript as described in the create-react-app docs and saw the same error.

Why is this happening for clean runs?

[jtremback]

I'm getting this issue as well, after installing the typescript template, and then installing reactstrap.

Was able to solve it by deleting node_modules and running npm install again

[brandonwaring]

@BrandonGardner2, you should run

npm install @types/react

to fix this issue. But I couldn't find where to add this package in this repo.

yea, it looked as if the @types/react failed to install in the initial creation. The dependency is created in the package.json. I just wiped node_modules in case anything else was missed.

luckily that is all that was needed haha.

I had the same issue. Adding and restarting the server fixed it.

[johnjesse]

I had this issue today - i think something is going on with yarn and npm

running

npm create react-app --template typescript foo

I can see I have foo/node_modules/@types/react

but after running

cd foo
npm install <package>

The types aren't there anymore

Investigating - I think this is because I have yarn installed globally - and CRA is therefore using yarn to install the deps - after running the npm install command I have both a yarn.lock and package-lock.json

Running

npm create react-app --template typescript foo --use-npm

initially - to force CRA to use npm seemed to fix this issue... is this just a weird conflict due to me using npm to create my react app and install deps - and CRA using global yarn to install deps?

[Dan503]

Quick fix for an already existing project:

npm i @types/react -D