Fibbonacier.js - Someone showed me a bad example of array restructuring yesterday. i thought this was prettier.

Fibbonacier.js

let Fibbonacier = function() {
    let cache = [1,1]
    let step = () => {
        let nums = [...cache]
        let [a,b] = [nums.pop() || 1, nums.pop() || 1]
        cache.push(a+b)
    }
    return {
        step : step,
        result: cache
    }
} 

let fib = Fibbonacier()
fib.step()
fib.step()
fib.step()
fib.step()
fib.step()
fib.step()
console.log(fib.result)