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@gaearon
gaearon / 00-README-NEXT-SPA.md
Last active March 23, 2023 13:56
Next.js SPA example with dynamic client-only routing and static hosting
View 00-README-NEXT-SPA.md

Next.js client-only SPA example

Made this example to show how to use Next.js router for a 100% SPA (no JS server) app.

You use Next.js router like normally, but don't define getStaticProps and such. Instead you do client-only fetching with swr, react-query, or similar methods.

You can generate HTML fallback for the page if there's something meaningful to show before you "know" the params. (Remember, HTML is static, so it can't respond to dynamic query. But it can be different per route.)

Don't like Next? Here's how to do the same in Gatsby.

@gaearon
gaearon / connect.js
Last active March 21, 2023 13:59
connect.js explained
View connect.js
// connect() is a function that injects Redux-related props into your component.
// You can inject data and callbacks that change that data by dispatching actions.
function connect(mapStateToProps, mapDispatchToProps) {
// It lets us inject component as the last step so people can use it as a decorator.
// Generally you don't need to worry about it.
return function (WrappedComponent) {
// It returns a component
return class extends React.Component {
render() {
return (
@gaearon
gaearon / modern_js.md
Last active March 20, 2023 21:09
Modern JavaScript in React Documentation
View modern_js.md

If you haven’t worked with JavaScript in the last few years, these three points should give you enough knowledge to feel comfortable reading the React documentation:

  • We define variables with let and const statements. For the purposes of the React documentation, you can consider them equivalent to var.
  • We use the class keyword to define JavaScript classes. There are two things worth remembering about them. Firstly, unlike with objects, you don't need to put commas between class method definitions. Secondly, unlike many other languages with classes, in JavaScript the value of this in a method [depends on how it is called](https://developer.mozilla.org/en-US/docs/Web/Jav
@gaearon
gaearon / index.html
Last active March 19, 2023 13:24
Multiple React components on a single HTML page
View index.html
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title>Add React in One Minute</title>
</head>
<body>
<h2>Add React in One Minute</h2>
<p>This page demonstrates using React with no build tooling.</p>
@gaearon
gaearon / prepack-gentle-intro-1.md
Last active March 18, 2023 07:54
A Gentle Introduction to Prepack, Part 1
View prepack-gentle-intro-1.md

Note:

When this guide is more complete, the plan is to move it into Prepack documentation.
For now I put it out as a gist to gather initial feedback.

A Gentle Introduction to Prepack (Part 1)

If you're building JavaScript apps, you might already be familiar with some tools that compile JavaScript code to equivalent JavaScript code:

  • Babel lets you use newer JavaScript language features, and outputs equivalent code that targets older JavaScript engines.
View quiz.md

A top-level App component returns <Button /> from its render() method.

  1. What is the relationship between <Button /> and this in that Button’s render()?

  2. Does rendering <Button><Icon /></Button> guarantee that an Icon mounts?

  3. Can the App change anything in the Button output? What and how?


@gaearon
gaearon / Wordle.js
Created January 22, 2022 20:49
wordle v3 (tiny wordle clone i built during a stream) https://www.youtube.com/watch?v=Qxn4-bTOx0g
View Wordle.js
import { useState, useEffect, useRef, useMemo } from 'react'
export default function Wordle() {
let [currentAttempt, setCurrentAttempt] = useState('')
let [bestColors, setBestColors] = useState(() => new Map())
let [history, setHistory] = usePersistedHistory(h => {
waitForAnimation(h)
})
useEffect(() => {
@gaearon
gaearon / minification.md
Last active March 17, 2023 19:34
How to Set Up Minification
View minification.md

In production, it is recommended to minify any JavaScript code that is included with your application. Minification can help your website load several times faster, especially as the size of your JavaScript source code grows.

Here's one way to set it up:

  1. Install Node.js
  2. Run npm init -y in your project folder (don't skip this step!)
  3. Run npm install terser

Now, to minify a file called like_button.js, run in the terminal:

@gaearon
gaearon / uselayouteffect-ssr.md
Last active March 16, 2023 21:06
useLayoutEffect and server rendering
View uselayouteffect-ssr.md

If you use server rendering, keep in mind that neither useLayoutEffect nor useEffect can run until the JavaScript is downloaded.

You might see a warning if you try to useLayoutEffect on the server. Here's two common ways to fix it.

Option 1: Convert to useEffect

If this effect isn't important for first render (i.e. if the UI still looks valid before it runs), then useEffect instead.

function MyComponent() {
@gaearon
gaearon / index.html
Last active March 12, 2023 14:56
Add React in One Minute
View index.html
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title>Add React in One Minute</title>
</head>
<body>
<h2>Add React in One Minute</h2>
<p>This page demonstrates using React with no build tooling.</p>