async-challenges.js

/* CHALLENGE 1 */

function sayHowdy() {
  console.log('Howdy');
}

function testMe() {
  setTimeout(sayHowdy, 0);
  console.log('Partnah');
}
// After thinking it through, uncomment the following line to check your guess!
// testMe(); // what order should these log out? Howdy or Partnah first?


/* CHALLENGE 2 */

function delayedGreet() {
  setTimeout(() => {console.log('welcome');}, 3000);
}
 
// Uncomment the following line to check your work!
// delayedGreet(); // should log (after 3 seconds): welcome


/* CHALLENGE 3 */

function helloGoodbye() {
  setTimeout(() => {console.log("good bye")}, 2000)
  console.log("hello");
}
// Uncomment the following line to check your work!
// helloGoodbye(); // should log: hello // should also log (after 3 seconds): good bye


/* CHALLENGE 4 */

function brokenRecord() {
  setInterval(() => {console.log("hi again")}, 1000)
}
// Uncomment the following line to check your work!
// brokenRecord(); // should log (every second): hi again


/* CHALLENGE 5 */

function limitedRepeat() {
		let timerId = setInterval(() => console.log("hi for now"), 1000);
    setTimeout(() => clearInterval(timerId), 5000);
}

// Uncomment the following line to check your work!
// limitedRepeat(); // should log (every second, for 5 seconds): hi for now


/* CHALLENGE 6 */

function everyXsecsForYsecs(func, int, dur) {
	let timerId = setInterval(() => func(), int*1000);
  setTimeout(()=> clearInterval(timerId), dur*1000);
}
// Uncomment the following lines to check your work!
// function theEnd() {
//   console.log('This is the end!');
// }
// everyXsecsForYsecs(theEnd, 2, 20); // should invoke theEnd function every 2 seconds, for 20 seconds): This is the end!


/* CHALLENGE 7 */

function delayCounter(target, wait) {
	return (() => {
    	let i=0;
      let timerId = setInterval(() => { i++; console.log(i)}, wait);
  		setTimeout(()=> clearInterval(timerId), target*1000);
  })
}

// UNCOMMENT THESE TO TEST YOUR WORK!
// const countLogger = delayCounter(3, 1000)
// countLogger();
// After 1 second, log 1
// After 2 seconds, log 2
// After 3 seconds, log 3

/* CHALLENGE 8 */
function promised (val) {
	return new Promise((resolve) => {
    setTimeout(()=> resolve(val), 2000)
  })

}

// UNCOMMENT THESE TO TEST YOUR WORK!
// const createPromise = promised('wait for it...');
// createPromise.then((val) => console.log(val)); 
// will log "wait for it..." to the console after 2 seconds

/* CHALLENGE 9 */

class SecondClock {
  constructor(cb) {
    this.cb = cb;
  }
  start(){ this.timerId = setInterval(()=>{ 
    if(this.cb >= 60) this.cb = 0;
    this.cb++; 
    console.log(this.cb) 
  }, 1000)}

	reset(){this.cb = 0; clearInterval(this.timerId)}   
}



// UNCOMMENT THESE TO TEST YOUR WORK!
// const clock = new SecondClock(58);
// console.log("Started Clock.");
// clock.start();
// setTimeout(() => {
//     clock.reset();
//     console.log("Stopped Clock after 6 seconds.");
// }, 6000);

/* CHALLENGE 10 */
const debounce = (callback, interval) => {
  let timerStart = new Date();
  return () => {
    const invocationTime = new Date();
    if (invocationTime - timerStart > interval) {
      timerStart = new Date();
      return callback();
    }
  };
};


// UNCOMMENT THESE TO TEST YOUR WORK!
// function giveHi() { return 'hi' }
// const giveHiSometimes = debounce(giveHi, 3000);
// console.log(giveHiSometimes()); // -> 'hi'
// setTimeout(function() { console.log(giveHiSometimes()); }, 2000); // -> undefined
// setTimeout(function() { console.log(giveHiSometimes()); }, 4000); // -> undefined
// setTimeout(function() { console.log(giveHiSometimes()); }, 8000); // -> 'hi'