Discussion on: Share a code snippet in any programming language and describe what's going on

View post

Replies for: I'll go first with Ruby class String def like_a_cow "Moo #{self} mooooo" end end "Hello".like_a_cow => "Moo Hello mooooo" Ente...

In Rust you can add functions to other types with traits. This actually adds the like_a_cow function for all types that are printable, including strings. You have to use the trait though.

pub trait LikeACow {
    fn like_a_cow(&self) -> String;
}

impl<T: std::fmt::Display> LikeACow for T {
    fn like_a_cow(&self) -> String {
        format!("Moo {} mooooo", &self)
    }
}

fn main() {
    // need to `use LikeACow;` if used in other modules, but not here.
    let s = "hello";
    println!("{}", s.like_a_cow());
}