tevko

const toggle = document.querySelectorAll(".switch input");

      toggle.forEach((el) =>
        el.addEventListener("click", (e) => {
          const isPressed = el.getAttribute("aria-pressed");
          el.setAttribute(
            "aria-pressed",
            // this part is tricky for humans cause "false" === true, since a non empty string is truthy in js 
            isPressed === "false" ? "true" : "false"
          );

tevko

// https://www.codewars.com/kata/556206664efbe6376700005c/solutions/javascript/me/best_practice

const isPolydivisible = (n, b) => n.toString().split('').every(
  (d, i, a) => (a.join('').slice(0, i + 1))
  .split('').reverse()
  .map(num => Number(num) || CHARS.indexOf(num))
  .reduce((a, c, i) =>
    (c * (Math.pow(b, i))) + Number(a)
  )
  % (i + 1) === 0

tevko

function formatDuration (seconds) {
  if (seconds === 0) {
    return 'now';
  }
  const dif = seconds * 1000;
  const difSeconds =  Math.floor(dif / 1000) % 60;
  const difMinutes =  Math.floor(dif / 60000) % 60;
  const difHours =  Math.floor(dif / 3.6e+6) % 24;
  const difDays =  Math.floor(dif / 8.64e+7) % 365;
  const difYears = Math.floor(dif / 3.154e+10);

tevko

Let's say I have an array of 8 objects. Each object represents a task which can be completed multiple times. 
In this case, the goal is to complete each task as many times as possible, until the allotted time per task is up
and I must move on to the next task. Let's also say that I have a total of ten minutes (600 seconds) to spend on
all tasks combined. Using javascript, how can I assign a random number of seconds (no less than 45, assuming each
task takes a minimum of 45 seconds to complete once) to each object so that the combined total of seconds adds up
to exactly 600? In other words, how do I split 600 into 8 random numbers where each random number is >= 45, and
all combined numbers add to 600?

tevko

self.addEventListener('install', function(event) {
    // Perform install steps
    event.waitUntil(
        caches.open(BB_SW_CACHE_NAME)
        .then(function(cache) {
            BB_urlsToCache.map(function(url) {
                var request = new Request(url, {mode: 'no-cors'});

                fetch(request).then(function(response) {
                    return caches.open(BB_SW_CACHE_NAME).then(function(c) {

tevko

  const rm = new Map([
    ['I', 1],
    ['II', 2],
    ['III', 3],
    ['IV', 4],
    ['V', 5],
    ['VI', 6],
    ['VII', 7],
    ['VIII', 8],
    ['IX', 9],

tevko

Array.apply(null, document.querySelectorAll('*')).map(function(e, i, a) {
    var message;
    
    try {
      document.createElement(e.nodeName);
      message = e.nodeName + ' supports document.createElement';
    } catch (e) {
      message = e.nodeName + ' does not support document.createelement'; 
    }
    return message

tevko

var findParentAttribute = function(id, ctx) {
  if (ctx.hasAttribute(id)) {
  	return ctx.getAttribute(id);
  } else {
  	return this.findParentAttribute(id, ctx.parentElement)
  }
  return false
}

findParentAttribute('foo', document.querySelector('div').parentElement) // will traverse dom to find parent element with data attribute

tevko

// "Bitwise operators perform their operations on such binary representations, but they return standard JavaScript numerical values."

//It transforms -1 into 0, and 0 is false in javascript, so:

var someText = 'text';
!!~someText.indexOf('tex'); //sometext contains text - true
!~someText.indexOf('tex'); //sometext not contains text - false
~someText.indexOf('asd'); //sometext contains asd - false
~someText.indexOf('ext'); //sometext contains ext - true

tevko

var trigger = function trigger(eventName, elem, data) {
    var evt;
    data = data || undefined;
    try {
        evt = new CustomEvent(eventName, {detail: data});
    } catch (e) {
        evt = document.createEvent('CustomEvent');
        evt.initCustomEvent(eventName, true, true, data);
    }
    elem.dispatchEvent(evt);