danielcardeenas

/**
 * Puts a timeout to given promise.
 * Will not error out. Instead will return given fallback value
 * @param source
 * @param time
 * @param fallbackTo
 * @returns
 */
export function withTimeout<T>(
  source: Promise<T>,

danielcardeenas

/**
 * Groups array by given key
 * @param items
 * @param fn
 * @returns
 */
function groupBy<T, K extends string | number>(
  items: T[],
  fn: (item: T) => K,
): { [key: string]: T[] } {

danielcardeenas

// 1. Get a random boolean (true/false)
const randomBoolean = () => Math.random() >= 0.5;
randomBoolean();
// Result: a 50/50 change on returning true of false

// 2. Check if the provided day is a weekday
const isWeekday = (date) => date.getDay() % 6 !== 0;
isWeekday(new Date(2021, 0, 11));
// Result: true (Monday)
// Result: false (Sunday)

danielcardeenas

// thanks @david

var arrays = [[1], [1], [1,2], [1]];
function combos(list, currentIndex = 0, combinations = [], current = []) {
  if (currentIndex === list.length) {
    combinations.push(current);
  } else {
    for (var item of list[currentIndex]) {
      combos(list, currentIndex + 1, combinations, [...current, item]);
    }