Code shared from the Rust Playground

playground.rs

#![allow(unused)]
trait Foo {
    fn bar(&self);
    fn baz(&self);
}
struct MyStruct;

impl Foo for MyStruct {
    fn bar(&self) {
        let mut d = vec!["a", "b", "c", "d","e","f","g","h", "i", "l", "m"];
        d.sort_by(|a, b| a.partial_cmp(b).unwrap());
        
        let mut  s = vec!["c", "b", "a"];
        s.sort_by(|a, b| a.partial_cmp(b).unwrap());
        
        let u = d.clone().into_iter()
            .map(|x| s.binary_search(&x).and_then(|i| d.get(i).ok_or(0))).map(|y|y.unwrap_or(&" ")).collect::<Vec<_>>();
        println!("==> {:#?}", u);        
    }

    fn baz(&self) {
        // let's not worry about implementing baz() for now
        todo!();
    }
}

fn main() {
    let s = MyStruct;
    s.bar();

    // we aren't even using baz() yet, so this is fine.
}