adding-typescript.md

id	title
adding-typescript	Adding TypeScript

Note: this feature is available with react-scripts@2.1.0 and higher.

TypeScript is a typed superset of JavaScript that compiles to plain JavaScript.

To start a new Create React App project with TypeScript, you can run:

npx create-react-app my-app --typescript

# or

yarn create react-app my-app --typescript

If you've previously installed create-react-app globally via npm install -g create-react-app, we recommend you uninstall the package using npm uninstall -g create-react-app to ensure that npx always uses the latest version.

To add TypeScript to a Create React App project, first install it:

npm install --save typescript @types/node @types/react @types/react-dom @types/jest

# or

yarn add typescript @types/node @types/react @types/react-dom @types/jest

Next, rename any file to be a TypeScript file (e.g. src/index.js to src/index.tsx) and restart your development server!

Type errors will show up in the same console as the build one. You'll have to fix these type errors before you continue development or build your project. For advanced configuration, see here.

To learn more about TypeScript, check out its documentation.

Note: If your project is not created with TypeScript enabled, npx may be using a cached version of create-react-app. Remove previously installed versions with npm uninstall -g create-react-app (see #6119).

Note: You are not required to make a tsconfig.json file, one will be made for you. You are allowed to edit the generated TypeScript configuration.

Note: If you are currently using create-react-app-typescript, see this blog post for instructions on how to migrate to Create React App.

Note: We recommend using VSCode for a better integrated experience.

Note: Constant enums and namespaces are not supported.