Mike Vardy mike-at-redspace

The useImperativeHandle hook can be useful in advanced scenarios where you need to provide a custom instance to the parent of a functional component that is wrapped in a forwardRef.

For example, suppose you have a TextInput component that is implemented as a functional component and wrapped in a forwardRef so that it can be used like this:

const TextInput = React.forwardRef((props, ref) => {
  // The TextInput component implementation goes here
});

// Use the TextInput component with a ref

The useDebugValue hook can be useful in advanced scenarios where you want to provide a custom string representation of a value for the React DevTools profiler. This can be useful for debugging and optimizing performance in complex applications.

For example, suppose you have a custom hook called useFormattedDate that returns the current date and time in a specific format. Here is an example of how this hook could be implemented:

function useFormattedDate() {
  const [date, setDate] = useState(new Date());

  useEffect(() => {
 const interval = setInterval(() =&gt; {

	import React, { useRef } from 'react'

	const App = () => {
	const sectionRefs = [useRef(null), useRef(null), useRef(null)]

	const activeSection = useScrollSpy({
	sectionElementRefs: sectionRefs,
	offsetPx: -80
	})

	import React from 'react';
	import styled from '@emotion/styled';

	const FlexboxWrapper = styled.div`
	display: flex;
	flex-direction: ${props => props.direction \|\| 'row'};
	align-items: ${props => props.alignItems \|\| 'stretch'};
	justify-content: ${props => props.justifyContent \|\| 'flex-start'};
	`;

	import React, { useState, useEffect } from 'react'

	const useWebWorker = (workerUrl, callback) => {
	const [worker, setWorker] = useState(null)

	useEffect(() => {
	if (workerUrl) {
	const newWorker = new Worker(workerUrl)
	setWorker(newWorker)
	}

	{
	"v": "5.7.4",
	"fr": 29.9700012207031,
	"ip": 0,
	"op": 233.000009490285,
	"w": 1920,
	"h": 1080,
	"nm": "3_24_LOGO_CLOSER 2",
	"ddd": 0,
	"assets": [

	function cheapStringify(object) {
	if (typeof object !== 'object' \|\| object === null) {
	if (typeof object === 'string') {
	return `"${object.replace(/"/g, '\\"')}"`
	}
	return String(object)
	}
	let result = '{'
	for (const key in object) {
	result += `"${key.replace(/"/g, '\\"')}":${stringify(object[key])},`

	/*
	## All functions return a number, which is guaranteed to start at 0 and end at 1

	f(t), where t in [0..1]

	f(0) -> 0
	f(1) -> 1

	*/
	export const easing = {

	Usage

	console.save(data, [filename])

	Data can be a string or just an object, objects are passed through json.stringify() before writing to file.

	Filename is optional, defaults to ‘console.json’.

	while True:
	try:
	subtrack = int(input("Enter a digit between 1 and 10 to subtract: "))
	if subtrack < 0:
	print("Please enter a positive number")
	continue
	elif 0 < subtrack <= 10:
	break
	else:
	print("Please enter a number between 1 and 10")