Shared via Rust Playground

playground.rs

#![feature(type_macros)] 
 
#[derive(Debug)]
struct Tuple<T, N> {
   data: T,
   next: N,
}
macro_rules! tuple {
    ($y:ty, $($x:ty),+) => {
        Tuple<$y, tuple!($($x),+)>
    };
    ($y:ty) => {$y};
}

macro_rules! mk_tuple {
    ($y:expr, $($x:expr),+) => {
        Tuple{ data: $y, next: mk_tuple!($($x),+) }
    };
    ($y:expr) => {$y};
}

#[derive(Debug)]
struct Foo(u8);
#[derive(Debug)]
struct Bar(u8);
#[derive(Debug)]
struct Baz(u8);

fn main() {
   let x = mk_tuple!(Foo(3), Bar(4), Baz(5)); 
   print_my_tuple(x);
}

fn print_my_tuple(tup: tuple!(Foo, Bar, Baz)) { // can specify it as a type too
    println!("{:?}", tup)
}