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Comment by WhitneyLand | Hacker News Reader

Developer learning curve: The context name is a good choice I think. Context API sounds much more elegant than global variables API.

While that’s a little tongue in cheek, the lifecycle method names I would rate as a drastic drop in intuitiveness:

  componentWillMount

  componentWillReceiveProps

  componentWillUpdate

New:

  getDerivedStateFromProps

  getSnapshotBeforeUpdate

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This is intentional because those are relatively rare use cases. We want them to stand out and be quite specific about what they're doing.

You still have `componentDidMount`, `componentDidUpdate`, and `componentWillUnmount` that should be used more commonly and do exactly what you expect them to.

In your experience, what are the kind of things that people do in `componentWillMount` that they shouldn't be doing? Is it correct to say that `getSnapshotBeforeUpdate` is named to indicate what you were supposed to use `componentWillMount` for?

Thanks to you and brianvaughn for answering so many questions.

> In your experience, what are the kind of things that people do in `componentWillMount` that they shouldn't be doing?

The biggest one is probably adding event listeners or setting up subscriptions (which can cause memory leaks).

Here are some others: https://github.com/reactjs/rfcs/blob/master/text/0006-static...

> Is it correct to say that `getSnapshotBeforeUpdate` is named to indicate what you were supposed to use `componentWillMount` for?

No. `getSnapshotBeforeUpdate` is not really related to `componentWillMount`. It relates more to what people were using `componentWillUpdate` for.

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