bendc

const assign = (target, key, value) =>                                                                                                                                                   
  Object.assign(target, Object(key) === key ? key : {[key]: value});

bendc

const union = (...sets) =>
  sets.reduce((acc, set) => {
    set.forEach(val => acc.add(val));
    return acc;
  }, new Set);

const intersection = (...sets) =>
  sets.reduce((acc, set) => {
    set.forEach(val => {
      if (sets.every(set => set.has(val)))

bendc

const list = (length, callback) =>
  Array.from({length}, (hole, index) => callback(index));

bendc

const trackTime = timing => {
  const now = performance.now();
  if (!timing.startTime) timing.startTime = now;
  const elapsed = now - timing.startTime;
  const {duration} = timing;
  if (duration != null && duration <= elapsed) timing.startTime = null;
  return elapsed;
};

const delay = (callback, duration) => {

bendc

"use strict";


// animation utils
// ===============

const trackTime = timing => {
  const now = performance.now();
  if (!timing.startTime) timing.startTime = now;
  const elapsed = now - timing.startTime;

bendc

"use strict";


// animation utils
// ===============

const trackTime = id => {
  const [entry] = performance.getEntriesByName(id);
  if (!entry) {
    performance.mark(id);

bendc

const delay = (callback, duration) => {
  const tick = () =>
    getProgress(time) < 1 ? requestAnimationFrame(tick) : callback();
  const time = {
    duration,
    id: requestAnimationFrame(tick)
  };
};

bendc

const trackTime = id => {
  const [entry] = performance.getEntriesByName(id);
  if (!entry) {
    performance.mark(id);
    return 0;
  }
  return performance.now() - entry.startTime;
};
                                                                                                                                                                                                                                                                                           
const getProgress = ({duration, id}) => {

bendc

// polygon's points
const shapes = {
  play: [85, 70, 180, 125, 180, 125, 85, 180],
  stop: [85, 85, 165, 85, 165, 165, 85, 165]
};

const tick = now => {
  // calculate the current position of each point
  const points = shapes.play.map((start, index) => {
    const end = shapes.stop[index];

bendc

const easeOut = progress =>
  Math.pow(--progress, 5) + 1;