SOURCE

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

function add(a, b) {
    console.log("add")
    return a + b
}

let addMemory = memoize(add, function(...res) {
    return JSON.stringify(res)
})
console.log(addMemory(10, 20))
console.log(addMemory(10, 20))