为存有Box<dyn T>的结构体实现Clone

问题描述：无法为以下结构体实现Clone：12pub trait GetName {3 fn get_name(&self) -> String;4}56#[device(Clone)]7struct Node{8 name: String,9 children: Vec<Box<dyn GetName>>10}参考链接stackoverflow how-to-clone-a-struct-storing-a-boxed-trait-object具体实现1// 先为GetName继承一个能clone的trait2pub trait GetName: NodeClone{3 fn get_name(&self) -> String;4}56//自定义一个clone,里面套默认clone7pub trait NodeClone {8 fn clone_box(&self) -> Box<dyn GetName>;9}1011//自定义clone接口，where限制这个NodeClone只是用在GetName上，12//如果不借助这个NodeClone,直接pub tarit GetName:Clone{}是不行的13//没法放在Box<>里14impl<T> NodeClone for T15where16 T: 'static + GetName + Clone,17{18 fn clone_box(&self) -> Box<dyn GetName> {19 Box::new(self.clone())20 }21}222324//为Box<dyn T>实现Clone,调用dyn GetName的自定义Clone25impl Clone for Box<dyn GetName> {26 fn clone(&self) -> Box<dyn GetName> {27 self.clone_box()28 }29}3031#[derive(Clone)]32pub struct Node {33 name: String,34 children: Vec<Box<dyn GetName>>//子元素只要能GetName就可以35}3637impl GetName for Node{38 fn get_name(&self) -> String{39 return self.name.clone();40 }41}4243impl Node{44 //将子元素的name拼起来打印45 pub fn print_children(&self)->String{46 let s = self.children.iter()47 .map(|n|n.get_name())48 .collect::<Vec<_>>()49 .join(",");50 format!("[{}]",s)51 }52}5354fn main() {5556 let a1= Box::new(Node{57 name: "a1111".to_string(),58 children:vec![]59 });60 let a2= Box::new(Node{61 name: "a2".to_string(),62 children:vec![]63 });6465 let b = Node{66 name: "bbb".to_string(),67 //测试一下，to_vec()会调用每个元素的Clone68 //a1、a2具体类型是Node,具有GetName、Clone接口，69 children:[a1 as Box<dyn GetName>,a2 as Box<dynGetName>].to_vec()70 };7172 println!("b={}",b.print_children());737475}