Vladimir Kuznetsov mistakster

Implement a form

Description

Develop a React form using react-hook-form to capture user input for a name field and position coordinates. The position is selected by clicking inside a rectangular block or by adjusting X and Y sliders. The form should submit data to the server via fetch().

Data Model

Optimizing performance of the React list component

Basically, everything need to be done in shouldComponentUpdate() method.

import React, {Component} from 'react';

class Item extends Component {
  shouldComponentUpdate(nextProps, nextState) {
 // always re-render component

	// The objective is to properly implement `ControlProps`.

	const Control = (props: ControlProps) => {
	const { variant, ...rest } = props;

	if (variant === "button") {
	return (
	<button {...rest} />
	);
	} if (variant === "link") {

	import { useState } from 'react';

	const Page = () => {
	const [value, setValue] = useState(0);

	return (
	<Counter
	value={value}
	increase={() => setValue(value + 1)}
	/>

	/**
	* The memory usage logger for a Node.js process
	*
	* Resident Set Size (RSS) is the amount of space occupied in the main memory
	* device for the process, which includes the heap, code segment and stack.
	* Variables are stored in the stack and the actual JavaScript code resides in the code segment.
	*
	* The heap is where objects, strings, and closures are stored.
	*
	* @see https://nodejs.org/api/process.html#process_process_memoryusage

	(function () {
	const dateFormat = d3.time.format('%Y-%m');

	// produce mock data
	function generateData() {
	const generator = new MersenneTwister(123456);
	const startDate = +new Date('2016-01-01');
	const endDate = +new Date('2017-01-01');

	return _.range(100)

	function toArray(obj) {
	return [].slice.apply(obj);
	}

	module.exports = function promisify(fn) {
	return function () {
	const args = toArray(arguments);
	const self = this;

	return new Promise(function (resolve, reject) {

	const RawSource = require('webpack-sources').RawSource;
	const postcss = require('postcss');

	const MASK = /\.css$/;

	/**
	* @param {Function} options.predicate is a function invoked per CSS file
	* @param {String} options.suffix is a string attached to the new file
	* @param {Array} options.pipeline is a list of PostCSS plugins
	* @param {Object} options.map is a PostCSS source maps configuration

	// Conver scale factor into pixels
	.fontScale(@scale: 0) {
	@list: 14px, 16px, 20px, 24px, 28px, 34px, 41px, 50px, 60px;

	.test-args(@scale) when (@scale >= -2) and (@scale <= 6) {
	font-size: extract(@list, @scale + 3);
	}

	.test-args(@scale);
	}