FIZZBUZZ!!!

fizzbuzz.rs

use std::fmt;

trait Fizzbuzzable {
    fn next(&self) -> Box<Fizzbuzzable>;
    fn string(&self) -> String;
}

struct A1(i64);
struct A2(i64);
struct A3(i64);
struct B1(i64);
struct B2(i64);
struct C1(i64);
struct D1(i64);
struct D2(i64);
struct D3(i64);
struct E1(i64);
struct F1(i64);
struct F2(i64);
struct G1(i64);
struct G2(i64);
struct G3(i64);

impl Fizzbuzzable for A1 {
    fn next(&self) -> Box<Fizzbuzzable> {
        let A1(i) = *self;
        Box::new(A2(i + 1)) as Box<Fizzbuzzable>
    }
    fn string(&self) -> String {
        let A1(i) = *self;
        fmt::format(format_args!("{}", i))
    }
}

impl Fizzbuzzable for A2 {
    fn next(&self) -> Box<Fizzbuzzable> {
        let A2(i) = *self;
        Box::new(A3(i + 1)) as Box<Fizzbuzzable>
    }
    fn string(&self) -> String {
        let A2(i) = *self;
        fmt::format(format_args!("{}", i))
    }
}

impl Fizzbuzzable for A3 {
    fn next(&self) -> Box<Fizzbuzzable> {
        let A3(i) = *self;
        Box::new(B1(i + 1)) as Box<Fizzbuzzable>
    }
    fn string(&self) -> String {
        "fizz ".to_string()
    }
}

impl Fizzbuzzable for B1 {
    fn next(&self) -> Box<Fizzbuzzable> {
        let B1(i) = *self;
        Box::new(B2(i + 1)) as Box<Fizzbuzzable>
    }
    fn string(&self) -> String {
        let B1(i) = *self;
        fmt::format(format_args!("{}", i))
    }
}

impl Fizzbuzzable for B2 {
    fn next(&self) -> Box<Fizzbuzzable> {
        let B2(i) = *self;
        Box::new(C1(i + 1)) as Box<Fizzbuzzable>
    }
    fn string(&self) -> String {
        "buzz ".to_string()
    }
}

impl Fizzbuzzable for C1 {
    fn next(&self) -> Box<Fizzbuzzable> {
        let C1(i) = *self;
        Box::new(D1(i + 1)) as Box<Fizzbuzzable>
    }
    fn string(&self) -> String {
        "fizz ".to_string()
    }
}

impl Fizzbuzzable for D1 {
    fn next(&self) -> Box<Fizzbuzzable> {
        let D1(i) = *self;
        Box::new(D2(i + 1)) as Box<Fizzbuzzable>
    }
    fn string(&self) -> String {
        let D1(i) = *self;
        fmt::format(format_args!("{}", i))
    }
}

impl Fizzbuzzable for D2 {
    fn next(&self) -> Box<Fizzbuzzable> {
        let D2(i) = *self;
        Box::new(D3(i + 1)) as Box<Fizzbuzzable>
    }
    fn string(&self) -> String {
        let D2(i) = *self;
        fmt::format(format_args!("{}", i))
    }
}

impl Fizzbuzzable for D3 {
    fn next(&self) -> Box<Fizzbuzzable> {
        let D3(i) = *self;
        Box::new(E1(i + 1)) as Box<Fizzbuzzable>
    }
    fn string(&self) -> String {
        "fizz ".to_string()
    }
}

impl Fizzbuzzable for E1 {
    fn next(&self) -> Box<Fizzbuzzable> {
        let E1(i) = *self;
        Box::new(F1(i + 1)) as Box<Fizzbuzzable>
    }
    fn string(&self) -> String {
        "buzz ".to_string()
    }
}

impl Fizzbuzzable for F1 {
    fn next(&self) -> Box<Fizzbuzzable> {
        let F1(i) = *self;
        Box::new(F2(i + 1)) as Box<Fizzbuzzable>
    }
    fn string(&self) -> String {
        let F1(i) = *self;
        fmt::format(format_args!("{}", i))
    }
}

impl Fizzbuzzable for F2 {
    fn next(&self) -> Box<Fizzbuzzable> {
        let F2(i) = *self;
        Box::new(G1(i + 1)) as Box<Fizzbuzzable>
    }
    fn string(&self) -> String {
        "fizz ".to_string()
    }
}

impl Fizzbuzzable for G1 {
    fn next(&self) -> Box<Fizzbuzzable> {
        let G1(i) = *self;
        Box::new(G2(i + 1)) as Box<Fizzbuzzable>
    }
    fn string(&self) -> String {
        let G1(i) = *self;
        fmt::format(format_args!("{}", i))
    }
}

impl Fizzbuzzable for G2 {
    fn next(&self) -> Box<Fizzbuzzable> {
        let G2(i) = *self;
        Box::new(G3(i + 1)) as Box<Fizzbuzzable>
    }
    fn string(&self) -> String {
        let G2(i) = *self;
        fmt::format(format_args!("{}", i))
    }
}

impl Fizzbuzzable for G3 {
    fn next(&self) -> Box<Fizzbuzzable> {
        let G3(i) = *self;
        Box::new(A1(i + 1)) as Box<Fizzbuzzable>
    }
    fn string(&self) -> String {
        "fizzbuzz ".to_string()
    }
}

fn main() {
    let limit = 100;
    let mut v = Box::new(A1(1)) as Box<Fizzbuzzable>;

    for _ in 0..limit {
        println!("{}", v.string());
        v = v.next();
    }
}