- Check for an existing
.gitignore
file in the project directory
ls -a
A Pen by Tony Brown on CodePen.
React recently introduced an experimental profiler API. This page gives instructions on how to use this API in a production release of your app.
Table of Contents
import { Component } from "React"; | |
export var Enhance = ComposedComponent => class extends Component { | |
constructor() { | |
this.state = { data: null }; | |
} | |
componentDidMount() { | |
this.setState({ data: 'Hello' }); | |
} | |
render() { |
Mute these words in your settings here: https://twitter.com/settings/muted_keywords | |
ActivityTweet | |
generic_activity_highlights | |
generic_activity_momentsbreaking | |
RankedOrganicTweet | |
suggest_activity | |
suggest_activity_feed | |
suggest_activity_highlights | |
suggest_activity_tweet |
function getFirstLast(array) { | |
const { | |
0: first, | |
length: len, | |
[len - 1]: last | |
} = array | |
return {first, last} | |
} |
// createContext | |
const WeatherContext = React.createContext({ day: 3 }) | |
const App = ({ children }) => { | |
const [weather, setWeather] = React.useState(null) | |
const [error, setError] = React.useState(null) | |
React.useEffect(() => { | |
api.getWeather(...) | |
.then(setWeather) | |
.catch(setError) | |
}, []) |
const bigArr = new Array(1000000).fill(1).map((_, i) => i); | |
bigArr[100] = 5; | |
const allUnique = arr => { | |
const all = new Set(); | |
for (let el of arr) { | |
if (all.has(el)) { | |
return false; | |
} |
/** Store Data */ | |
const prices = { | |
game: 59.95, | |
nintendo: 399.99, | |
controller: 49.99, | |
xbox: 299.99, | |
ps1: 349.99 | |
} | |
const basket = [ |
function greetCurried(greeting) { | |
return function(name) { | |
if (typeof(greeting) !== 'string') { | |
return ('Greetings!') | |
} else if (typeof(name) !== 'string') { | |
return (greeting) | |
} | |
return (`${greeting}, ${name}`) | |
} |