variadiz

Variadic function support for Rust.

Install

cargo add tuplez variadiz

Example

use variadiz::*;

#[variadic]
fn print<T, U>(counter: usize, non_variadic: T, others: Option<U>)
where
    T: std::fmt::Display,
    U: std::fmt::Debug,
{
    #[va_expand_ref(counter: usize)]
    {
        println!("{counter}: {:?}", others);
        *counter += 1;
    }
    #[va_expand_mut]
    {
        others.take();
    }
    #[va_expand(counter: usize, non_variadic: T)]
    {
        println!("[{non_variadic}] {counter}: {:?}", others);
        *counter += 1;
    }
}

print(
    0,
    20240429,
    va_args!(Some("hello"), Some(vec![1, 2, 3]), Some('e')),
);

Outputs:

0: Some("hello")
1: Some([1, 2, 3])
2: Some('e')
[20240429] 0: None
[20240429] 1: None
[20240429] 2: None

Check the documentation page for details.