trait_rust.rs

trait A {
    fn fn_a(&self) {
        println!("fna");
    }
}

trait B {
    fn fn_b(&self) {
        println!("fnb");
    }
}

trait C: A + B {}

struct St1{}
impl A for St1{}
impl B for St1{}
impl C for St1{}

struct St2{}
impl A for St2{}
impl B for St2{}
impl C for St2{}

fn main() {
    //let mut st_vec: Vec<Box<dyn A + B>> = Vec::new();
    let mut st_vec2: Vec<Box<dyn C>> = Vec::new();
    st_vec2.push(Box::new(St1{}));
    st_vec2.push(Box::new(St2{}));
    
    for s in st_vec2.iter() {
        s.fn_a();
        s.fn_b();
    }
}