[danabramov]

Note: createRef doesn’t replace callback refs. It just offers a more ergonomic API for common use cases.

There are still rarer cases where callback refs are useful. For example when you need to run a side effect on a node as it attaches and detaches.

Also note: legacy lifecycles are not deprecated yet. You won’t see the warnings unless you opt in with <StrictMode>. They will be officially deprecated in a future minor release when more libraries have had time to update.

[hoodoof]

Off topic but Dan - referring to your question to me yesterday I'm curious to your answer:

You asked "Curious, what do you use it for?" in regard to componentWillReceiveProps

https://news.ycombinator.com/item?id=16695064

I use componentWillReceiveProps for just about everything - I had thought it was a fundamental part of the Redux flow. i.e. Redux updates, new props flow through the hierarchy, I pick that up in componentWillReceiveProps and make changes based on new props.

Is this not correct?

[brianvaughn]

The purpose of componentWillReceiveProps was to update state in response to props changes. (This is also the purpose of getDerivedStateFromProps.)

What you're describing sounds more like you're updating something external (e.g. your Redux store). This isn't what the lifecycle is meant for, and you'd be better off using componentDidUpdate instead.

[spicyj]

Let's keep the discussion on that thread – I just responded there.