Rust: Traits

A trait is a collection of methods defined for an unknown type: Self. They can access other methods declared in the same trait, and can be implemented for any data type.

trait Foo<T> {
    fn new() -> Self;
    fn test(&self, s: &String);
}
struct Bar<T> {
    value: T
}

impl<T> Foo<T> for Bar<T>
where
    T: Sized
{
    fn new() -> Self {
        Bar {
            value: 1
        }
    }

    fn test(&self, s: &String) {
        println!(s);
    }
}
let bar: Bar = Bar::<i32>::new();
bar.test(format!("hello"));