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Import hooks into React Typescript

I am trying to implement hooks into a React (^16.6.0) application using TypeScript

import * as React, {useState}  from 'react';

Any idea what is the right syntax for this import?

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Alexandru Popa Avatar asked Nov 21 '18 14:11

Alexandru Popa


2 Answers

import supports a limited set of syntax variations.

It can be:

import React, {useState}  from 'react';

The downside is that entire library is imported, because React is default export and cannot be tree-shaken. Since the presence of React import is needed to use JSX syntax, a more efficient way is:

import * as React from 'react';
import {useState}  from 'react';

Hooks were introduced in pre-release React 16.7. react version constraint should be ^16.7.0-alpha.0, @types/react should be ^16.7.0.

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Estus Flask Avatar answered Oct 22 '22 17:10

Estus Flask


I had the same error on "@types/react": "^16.8.17". Looking at it's type def file, it was missing the useState function for some reason, though it was mentioned in the comments of other hooks like useReducer.

Upgrading to "@types/react": "^16.8.18" with npm i @types/react@latest fixed it.

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ratbeard Avatar answered Oct 22 '22 17:10

ratbeard