Function Group is a Function Overloading macro/hack for the rust programing language. The macro allows you to define multiple functions that take a variable number of arguments! Actually the functions still only take one argument, but they accept multiple types of tuples
```rust function_group! { fn add -> usize { (one : usize, two : usize) { one + two } (one : usize, two : usize, three: usize) { add((one, two)) + three } } }
assert!(add((5, 5)) == 10);
assert!(add((5, 5, 5)) == 15);
rust
functiongroup! {
fn addto {
(one : &mut usize, two : usize) {
*one += two;
}
(one : &mut usize, two : usize, three : usize) {
*one += two + three;
}
}
}
let mut x = 10; addto((&mut x, 5)); addto((&mut x, 5, 5)); assert!(x == 25); ```