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Issue using Hooks with exported component

See original GitHub issue


When I render an imported component which uses the useContext hook, I get the following error:

Uncaught TypeError: Cannot read property 'context' of undefined
    at Module.useContext (index.js:173)
    at d../src/example.tsx.exports.Example [as constructor] (example.tsx:7)

It appears that currentComponent is undefined, but I’m not sure what that means or how to fix it.

I think the issue is related to my build process, so have created a repository which demonstrates the problem.

Steps to reproduce

  1. Clone
  2. Run npm install
  3. Run npm run-script run

Expected behaviour

The number 5 is rendered on the page, inside of a H1.

Actual behaviour

When the Example component is rendered, the previously mentioned error is thrown.

Issue Analytics

  • State:closed
  • Created 4 years ago
  • Reactions:5
  • Comments:10 (5 by maintainers)

github_iconTop GitHub Comments

cristianbotecommented, Oct 1, 2019

Hey @artalar when using aliasing of react to preact/compat you should use react imports rather than preact. In other words, you should use import { useContext } from "react".

Check out the amended version

artalarcommented, Oct 1, 2019

@developit @marvinhagemeister 10.0.0-rc.3 - same bug.

(reproduce, see Header.tsx)

I try to import { useContext } from "preact/hooks"; and import { useContext } from "preact/compat";, but every time get the same error: TypeError: Cannot read property 'context' of undefined.

By the way, all works fine if I firstly start the server with code without hooks, and after that try to add code with hooks (hot reload -> all works fine). May be the problem related to SSR (next.js)?

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