JS: Memoize

memoize.js

function memoize(fn) {
    const cache = {};
    return function (...args) {
        //fast version of function
        if(cache[args]) {
            //if args are already in cache, return result
            return cache[args];
        } 

        //Use slow function
        const result = fn.apply(this, args);
        cache[args] = result;

        return result;
    };
}