struct PA;
struct PB;
struct PC;

struct Parts<A, B, C> {
    pub a: A,
    pub b: B,
    pub c: C,
}

fn create() -> Parts<PA, PB, PC> {
    Parts {
        a: PA,
        b: PB,
        c: PC,
    }
}

struct Led {
    p: PB,
}

impl Led {
    pub fn new<A, C>(parts: Parts<A, PB, C>) -> (Self, Parts<A, (), C>) {
        (
            Led {
                p: parts.b,
            },
            Parts {
                a: parts.a,
                b: (),
                c: parts.c,
            }
        )
    }
}

fn main() {
    let parts = create();

    let (led, parts) = Led::new(parts);

    // Second one fails
    let (led, parts) = Led::new(parts);
}