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Note

Highlights information that users should take into account, even when skimming.

Tip

Optional information to help a user be more successful.

Important

Crucial information necessary for users to succeed.

[!WARNING]

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export const memoizedAdd = () => {
  const cache = new Map();
  return (...args) => {
    const key = args.join();
    const cached = cache.get(key);
    if (cached) {
      console.log(`Returning cached value for ${key}`);
      return cached;
    } else {
      const result = args.reduce((total, val) => total + val);

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const a = new Promise(r => r({ a: 'A' }));
const b = new Promise(r => r({ b: 'B' }));
const c = new Promise(r => r({ c: 'C' }));
const result = (async () => {
  const abc = await Promise.all([a, b, c]);
  return abc.reduce((result, obj) => ({...result, ...obj}), {});
})();

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const ArrayUtils = [
  'map',
  'filter',
  'find',
]
.reduce((utils, method) => ({
  ...utils,
  [method]: (fn, arr) => arr ? arr[method](fn) : arr => arr[method](fn)
}), {})

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export default const renameProps = (map, obj) =>
  Object.entries(map).reduce((accum, [a, b]) => {
    delete accum[a]
    return obj[a] 
      ? Object.assign(accum, {[b]: obj[a]})
      : accum
  }, {...obj})

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/**
 * Tweens a number from `startValue` to `endValue` over the `duration` time period, 
 * calling `onAnimationFrame` on each animation frame.
 * 
 * @example 
 * // Tween to 100 from 0 over 2 seconds
 * tweenNumber(n => console.log(`step value: ${n}`), 100, 0, 2000);
 */
function tweenNumber (
  onAnimationFrame,

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module.exports = function leftpad (str, len, ch) {
  const val = String(str);
  const pad = ch === undefined ? ' ' : String(ch);
  return pad.repeat(Math.max(0, len - val.length), pad) + val;
};

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const zipObject = (keys, vals) => {
  return keys.reduce(
    (prev, val, i) => Object.assign(prev, { [val]: vals[i] }), {}
  )
}

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const toTitle = str => {
  return str.split(/[\W_]+/)
    .map(word => word.replace(/^\w/, first => first.toUpperCase()))
    .join(' ')
}

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export function callDeep (path, obj, ...args) {
  var fn = path.split('.').reduce((prev, curr) => prev[curr], obj)
  return fn.apply(obj, args)
}