griffinmichl

function sum(numbers, i = 0) {
  if (i === numbers.length) {
    return 0
  }
  return numbers[i] + sum(numbers, i+1)
}
console.log(sum([1,2,3,4,5]))


function sumTail(numbers, i = 0, sum = 0) {

griffinmichl

function debounce(func, wait) {
  let timeout
  return function(...args) {
    const context = this
    clearTimeout(timeout)
    timeout = setTimeout(() => func.apply(context, args), wait)
  }
}

function sayHello() {

griffinmichl

// still wrong 
function debounce(func, wait) {
  let timeout
  return (...args) => {
    const context = this
    clearTimeout(timeout)
    timeout = setTimeout(() => func.apply(context, args), wait)
  }
}

griffinmichl

function sayHello() {
  console.log('My name is', this.name)
}

const amy = {
  name: 'amy',
  speak: debounce(sayHello),
}

amy.speak()

griffinmichl

function sayHello(x) {
  console.log(x)
}

const debouncedSayHello = debounce(sayHello, 100)
debouncedSayHello(1)
debouncedSayHello(2)
debouncedSayHello(3)
setTimeout(() => debouncedSayHello(4), 200)

griffinmichl

// the wrong way
function debounce(func, wait) {
  let timeout
  return (...args) => {
    clearTimeout(timeout)
    timeout = setTimeout(() => func(...arg), wait)
  }
}

griffinmichl

const task1 = done => setTimeout(_ => {console.log('1'); done()}, 100)
const task2 = done => setTimeout(_ => {console.log('2'); done()}, 50)
const task3 = done => setTimeout(_ => {console.log('3'); done()}, 25)

const taskRunner1 = queue(1)

taskRunner1.push(task1)
taskRunner1.push(task2)
taskRunner1.push(task3)
// 1

griffinmichl

function queue(concurrency = 1) {
  let running = 0
  const taskQueue = []

  const runTask = (task) => {
    running++
    task(() => {
      running--
      if (taskQueue.length > 0) {
        runTask(taskQueue.shift())

griffinmichl

const fetchContent = (url) => {
  const timeDelay$ = Rx.Observable.timer(1000);
  const request$ =  Rx.Observable.create(observer =>
    fetch(url, { mode: 'no-cors' })
      .then(json => {
        console.log('test')
         observer.onNext(json)
         observer.onCompleted()
      })
      .catch(e => observer.onError())

griffinmichl

const fetchContent = (url) =>
    rx.Observable.create(observer => 
      fetch(url)
        .then(res => res.json())
        .then(json => {
          observer.onNext(json)
          observer.onCompleted()
        )
        .catch(e => observer.onError())
    )