I have a structure I'm planning to hand out in function calls instead a OnceCell as a global variable. I have a hash map in the structure which contains information needed by functions that get called. The trait contains functions to add to the hash map and convert the contents to a vector. I decided to get the information as a vector as I was unable to iterate the hash map. I found example of doing this but none worked. So I am trying to get the following code to work but it looks like having the information in the trait results in borrow problems. Can anyone suggest what I am doing wrong or it there a better way.

Here is the test code I am playing with -

use std::collections::HashMap;

#[derive(Debug)]
struct A {
    aa: String,
}

struct Mapper {
    map: HashMap<String, A>,
}
impl Mapper {
    fn new() -> Mapper {
        Mapper { map: HashMap::new(), }
    }
    fn convert(&self) -> Vec<&A> {
        let mut vec: Vec<&A> =  Vec::from_iter(self.map.values());
        vec
    }
    fn insert(mut self, name: String, item: A) {
        self.map.insert(name, item);
    }
}

fn main() {
    let mapper= Mapper::new();
    let myaa = A { aa: "aa".to_string() };
    let keya = "aa".to_string();
    mapper.insert(keya, myaa); 
    let x = mapper.convert();
    println!("{:?}", x);
}

fn convert(mapp: &HashMap<String, A>) -> Vec<&A> {
    let vec3 = Vec::from_iter(mapp.values());
    return vec3;
}

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