psynewave

const getDaysBetweenDates = (dateStart, dateEnd) => (new Date(dateEnd) - new Date(dateStart)) / (1000 * 3600 * 24);

getDaysBetweenDates('1/21/2020', '1/21/2021'); // 366 leap year
getDaysBetweenDates('1/21/2019', '1/20/2020'); // 365

getDaysBetweenDates(new Date('08/04/2020'), new Date('08/24/2020'));
getDaysBetweenDates('08/04/2020','08/24/2020');

psynewave

const take = (arr, n = 1, fromStart = true) => fromStart ? arr.slice(0, n) : n < 0 ? arr.slice(n) : arr.slice(-1 * n);
let fruits = ['Banana', 'Orange', 'Lemon', 'Apple', 'Mango']

take(fruits)
take(fruits, 3)
take(fruits, -3, false)
take(fruits, 3, false)

psynewave

const b64DecodeUnicode = (str) => decodeURIComponent(Array.prototype.map.call(atob(str),(c) => "%" + ("00" + c.charCodeAt(0).toString(16)).slice(-2)).join(""));

const parseJWT = (token) => JSON.parse(b64DecodeUnicode(token.split(".")[1].replace("-", "+").replace("_", "/")));

psynewave

const unescapeHTML = str =>
  str.replace(
    /&|<|>|'|"/g,
    tag =>
      ({
        '&': '&',
        '&lt;': '<',
        '&gt;': '>',
        '&#39;': "'",
        '&quot;': '"'

psynewave

const RSS_URL = `https://cors-anywhere.herokuapp.com/https://archive.org/services/collection-rss.php?collection=podcast_jeff-regan-the-great-detec_426081250`;

const xmlToJson = (xml) => {
  let obj = {};

  try {
    xml.hasChildNodes();
  } catch (err) {
    xml = new DOMParser().parseFromString(xml, "text/xml");
  }

psynewave

var checkIfObjectEmpty = obj => Object.keys(obj).length === 0 && obj.constructor === Object

psynewave

const apiURL = "https://pokeapi.co/api/v2/type/1";

const pokemonFetch = async () => {
	const initial = await fetch(apiURL);
	const initialJson = await initial.json();

	const detailsData = initialJson.pokemon.map(async i => {
		const preFetchData = await fetch(i.pokemon.url);
		return preFetchData.json();
	})

psynewave

const mergeTwoArrays = (a, b, unique = false) => unique != true ? a.concat(b) : [...new Set([...a, ...b])];

psynewave

const generateSeriesIntegers = len => [ ...Array(len).keys() ].map( i => i + 1);

psynewave

const sumOfSeries = arr => (arr.length * (parseInt(arr[0], 10) + parseInt(arr[arr.length -1], 10)))/2