memoize.js
export default function memoize(func, hasher) { var memoize = function(key) { var cache = memoize.cache; var address = '' + (hasher ? hasher.apply(this, arguments) : key); if (!has(cache, address)) cache[address] = func.apply(this, arguments); return cache[address]; }; memoize.cache = {}; return memoize; }