Rust

You must've read that wrong.

The first example, but formatted differently:

let value = "My name is Rho.";
let result = unformat!("My {} is {}.", value);

Now, result contains:

Some(("name", "Rho"))

...because the words "name" and "Rho" in value happened to be at the position of the {}-slots in the unformat!()-pattern.