# Tuple Structs If the field names are unimportant, you can use a tuple struct: ```rust,editable struct Point(i32, i32); fn main() { let p = Point(17, 23); println!("({}, {})", p.0, p.1); } ``` This is often used for single-field wrappers (called newtypes): ```rust,editable,compile_fail struct PoundsOfForce(f64); struct Newtons(f64); fn compute_thruster_force() -> PoundsOfForce { todo!("Ask a rocket scientist at NASA") } fn set_thruster_force(force: Newtons) { // ... } fn main() { let force = compute_thruster_force(); set_thruster_force(force); } ```
* Newtypes are a great way to encode additional information about the value in a primitive type, for example: * The number is measured in some units: `Newtons` in the example above. * The value passed some validation when it was created, so you no longer have to validate it again at every use: 'PhoneNumber(String)` or `OddNumber(u32)`. * Demonstrate how to add a `f64` value to a `Newtons` type by accessing the single field in the newtype. * Rust generally doesn’t like inexplicit things, like automatic unwrapping or for instance using booleans as integers. * Operator overloading is discussed on Day 3 (generics).