fibgen.js

/**
 * This is basic memoization. I am going to play around with it and come up with a few solutions!
 * Probably going to go back and rewrite this. Its kinda ugly.
 */
class Fib {
    constructor() {
        this.cache = {
            "10": [0,1,1,2,3,4,8,13, 21, 34]
        }

    }
    *fibGen(n = null, current = 0, next = 1) {
        
        const inifinite = !n && n !== 0;
        let firstN = n.toString();
        this.cache[firstN] = this.cache[firstN] || [];

        // ugly!
        if(this.cache[firstN] && this.cache[firstN].length === parseInt(firstN)) {
            // Due to the nature of Yield, cached is being called before it prints out the array. 
            // But, its only being printed once, so you know its working!
            console.log("Cached!");
            yield* this.cache[firstN];
            return;
        }

        while (inifinite || n--) {
            this.cache[firstN].push(current);
            yield current;
            [current, next] = [next, current + next];
        }
    }

}

module.exports = Fib;