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Comment by merb | Hacker News Reader

well 16.8 (which basically was the latest version)

also btw: https://reactjs.org/docs/hooks-faq.html#do-i-need-to-rewrite...

and I still have no idea how I only do stuff on the client in a SSR environment (stuff that i did in componentDidMount)

> and I still have no idea how I only do stuff on the client in a SSR environment (stuff that i did in componentDidMount)

The 'useEffect' hook - it won't be executed if you use e.g. ReactDOMServer.renderToString() for SSR

    useEffect(() => {
      console.log('Client side only');
    }, []);

Codesandbox: https://codesandbox.io/s/peaceful-dew-nvw83

While you wouldn't want to leave "console.log" in your code in production, you can use them in function components just like a classes' render methods.

A better example (from the video "React Today and Tomorrow and 90% Cleaner React With Hooks" from October[1]) is something along the lines of updating document.title = `${some} Page` or possibly calling an API.

[1]: https://www.youtube.com/watch?v=dpw9EHDh2bM

The console.log was only there to illustrate that the code in useEffect's callback is only being run on the client-side (see the codesandbox I linked to).

I think it's clear from the parent I was responding to that they have better use-cases in mind :)

Btw, totally agree about classes. I still like the 'look' of them for stateful components.

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