[mynameisvlad]

Isn’t it also explicitly discouraged with a warning because of how bad it could be?

The React docs are very clear on this:

> The render() function should be pure, meaning that it does not modify component state, it returns the same result each time it’s invoked, and it does not directly interact with the browser.

https://reactjs.org/docs/react-component.html#render

[nwienert]

It’s recommended now:

https://beta.reactjs.org/learn/you-might-not-need-an-effect#...

[mynameisvlad]

That’s such a weird 180 on their part considering how explicit they have been about it.

I guess they did a bunch of work to make the case work and are confident about it, but it just seems like such a weird decision considering they’ve been adamantly telling their devs not to do this for years.

[acemarke]

Calling `setState` while rendering has been a legitimate thing to do since hooks first came out, but _only_ in one specific scenario / usage pattern.

From the original hooks FAQ at time of release:

- https://reactjs.org/docs/hooks-faq.html#how-do-i-implement-g...

I talked about the reasoning / behavior for this in my React rendering guide:

- https://blog.isquaredsoftware.com/2020/05/blogged-answers-a-...

[mynameisvlad]

That still doesn’t change my comment.

It used to explicitly be a thing you must not do for years, it’s weird to go straight 180 on something you actively warn developers not to do. If it wasn’t well documented in the past, then that’s reasonable, but actively spitting out console warnings and explicit documentation warning against it is just going to mean that anyone who isn’t new to react is going to be extremely weary about it.

[aidos]

Interesting. Thanks for following up.