The Weird Things About React

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The video discusses various unique aspects and quirks in React, including the use of the Keyprop in React to remount components. This technique can be useful for resetting component state and lifecycle. FlushSync is another feature that allows state updates to be committed to the DOM before the browser paints, which can be crucial for operations like maintaining scroll position in chat applications. The video also highlights the ability for components to return undefined in React 18, providing more flexibility in component returns. React.FC in TypeScript is criticized for implicitly including children in the props type, leading to recommendations for explicit typing instead. The evolution of component composition in React is traced from mixins and higher-order components to render props and hooks, each with its own set of challenges and advantages. Additionally, the video touches on how React Lazy can be used with named exports, despite it typically requiring default exports. Lastly, the speaker mentions the Serenity app, which is similar to Notion or Confluence but offers end-to-end encryption and uses React and React Native for development.

From Author:

Conditional rendering issues in JSX, forwardRef, serveral ways to create refs, render props (yeah they still exist), higher-order components (do they still exist?), act, non-extendable classes, SuspenseList (well, maybe in 10 years), React.FC and of course our good old friend useEffect. All these weird things are part of our favourite library (not a framework™) and yet we still use and love it. Why actually? Let's talk about. Disclaimer: This is not a very serious talk, mostly…

This talk has been presented at React Advanced Conference 2022, check out the latest edition of this React Conference.

FAQ

React Native is used in Serenity to compile to Web and native iOS and Android apps, providing end-to-end encryption similar to platforms like Notion or Confluence.

Nick described the progression from React 0.14 as initially confusing due to the absence of version 1.0, but reassured by detailed blog posts explaining the versioning decisions. The later versions like 16, 17, and 18 brought stability and were well-received.

Yes, using the Keyprop to remount components in React is a technique discovered by Nick where changing the key value forces the component to remount, providing a way to reset component state and lifecycle.

FlushSync is used in React to commit state updates to the DOM before the browser paints, allowing for operations like scrolling to the last message in a chat application without waiting for the next paint cycle.

React 18 introduced the ability for components to return undefined to provide more flexibility in component returns, although the specific reasoning was not initially clear until further clarifications were made through community discussions.

Using React.FC in TypeScript was criticized for implicitly including children in the props type, which was not always desirable. This issue led to recommendations against using React.FC, favoring explicit typing of function components instead.

While React Lazy typically requires default exports, it is possible to use it with named exports through less straightforward methods, offering a solution for those preferring consistency in using named exports across their codebase.

Nik Graf
Nik Graf
33 min
21 Oct, 2022

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Video Transcription

Available in Español: Las Cosas Extrañas de React

1. Introduction to React and Serenity

Short description:

Today, we're going to talk about the weird things about React. I work on Serenity, a notion-like tool that is end-to-end encrypted. We use React and React Native for web, iOS, and Android development. I'm also an ACAD tutor and available for consulting or freelance work. Feel free to reach out.

Today, we're going to talk about the weird things about React. I'm Nick, short introduction. Yes, I work on Serenity. It's basically, think of this like a notion or confluence, but actually end to end encrypted. And of course, we use React, React Native, actually, in this case. So we compile to Web and React Native or iOS and Android App. And I'm also an ACAD tutor, so you can find some courses for me. And depending on who's asking, I'm either a consultant or freelance, so yeah. If you need some help, feel free to reach out.

2. React Journey and Interesting Features

Short description:

My journey with React started with version 0.12 or 0.13. I enjoyed using React and the official docs on twitter.com. Let me give you three examples of interesting things you may not know about React. One example is using the Keyprop to remount components.

Enough about me, well, not totally. Let's actually begin. My journey started with, I think, 0.12 or 0.13 with React. And that time was awesome. You know, you had this like create component class and React was very clear. And everything was good. Really enjoyed it.

Then 0.14 came along. And these were good times. And then came the first warning sign. What? Why not 1.0? Yeah, but they made this blog post, this like really, really long blog post about why they're doing this and basically explain Semver and so on. And I felt like, OK, so they probably, I mean why they're doing this, they must feel guilty. Or they must see that they're doing something wrong. And they're putting a lot of dedication in it. And so I'm fine with that. Let's move on. And after that, the world was OK again. 16, 17, 18, things are good. Yeah, the world is awesome.

And one thing that I really loved about React was the official docs, twitter.com. And you can really find a lot of great content there that you don't find on React.js or IG or so. Let me give you three examples. I'm going to run through this quickly and then get to more weird stuff. So did you know that you actually can use the Keyprop to remount components? This is a fantastic one. You don't find this anywhere. Well, there's one place. So what does this mean? Short, brief example. If you hit this application, it's very simple. It has a button. You can generate random IDs.

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