Mastering JavaScript Functional Programming

Simple memoization

We will work with the Fibonacci function we mentioned, which is a simple case: it receives a single numeric parameter. The function, as we saw it, was the following:

function fib(n) {    if (n == 0) {        return 0;    } else if (n == 1) {        return 1;    } else {        return fib(n - 2) + fib(n - 1);    }}

The solution we did there was general in concept, but particularly in its implementation: we had to directly modify the code of the function in order to take advantage of said memoization. Now we should look into a way of doing it automatically, in the same fashion as with other wrapped functions. The solution would be a memoize() function that wraps any other function, to apply memoization:

const memoize = fn => {    let cache = {};    return x => ...