JenniferFuBook

const curry = fn => {
    if (fn.length === 0) {
        return fn;
    }

    const _curry = (...args) => {
        if (fn.length <= args.length) {
            return fn.apply(null, args);
        }
        return _curry.bind(null, ...args);

JenniferFuBook

function mergeDeep(...objects) {

  // For simplicity, we ignore the cases for Date and Regex
  const isObject = obj => obj && typeof obj === 'object';

  return objects.reduce((prev, obj) => {
    try {
      Object.keys(obj).forEach(key => {
        const pVal = prev[key];
        const oVal = obj[key];

JenniferFuBook

function debounce(func, wait) {
  let current;
  return function (...args) {
    clearTimeout(current);
    current = setTimeout(() => func.apply(this, args), wait);
  }
}

// The message, 'Function is actually invoked', will be printed 1 second after the browser window stops resizing.
window.addEventListener('resize', debounce(()=>console.log('Function is actually invoked'), 1000));

JenniferFuBook

function throttle(func, limit) {
  let lastFunc;
  let lastRan;
  return function(...args) {
    if (!lastRan) {
      func.apply(this, args)
      lastRan = Date.now();
    } else {
      clearTimeout(lastFunc)
      lastFunc = setTimeout(() => {

JenniferFuBook

class App extends React.Component {
  constructor(props) {
    super(props)
    this.state = {
      value: 'highlight and copy me'
    }
    this.textInput = React.createRef();
    console.log(this.textInput);
    this.handleClick = this.handleClick.bind(this);
  }

JenniferFuBook

const App = () => {
  const [value, setValue] = React.useState('highlight and copy me');
  const textInput = React.useRef();
  
  const handleClick = () => {
    textInput.current.select();
    document.execCommand('copy');
  }
  
  return (

JenniferFuBook

const App = () => {
  ...
  const mounted = React.useRef(true);
  
  React.useEffect(() => {
    if (mounted.current) {
      some setState commands
    }
    
    return () => {

JenniferFuBook

class App extends React.Component {
  constructor(props) {
    super(props)
    this.state = {
      value: 'highlight and copy me'
    }
    this.handleClick = this.handleClick.bind(this);
  }
 
  handleClick() {

JenniferFuBook

const App = () => {
  const [value, setValue] = React.useState('highlight and copy me');
  let textInput;
  
  const handleClick = () => {
    textInput.select();
    document.execCommand('copy');
  }
  
  return (

JenniferFuBook

const MyTextInput = (props) => {
  return (
    <input {...props}/>
  );
};

const App = () => {
  const [value, setValue] = React.useState('highlight and copy me');
  const textInput = React.useRef('initialRef');