Sometimes, the Rust compiler cannot determine the size of a trait object at compile time. For example, if a function returns a trait object based on a condition, in such cases, impl Trait is not going to work. This is because the size of the trait object is not known at compile time. In such cases, you can use Box<dyn Trait> to return a trait object.
Box<T> lets you allocate memory on the heap and store the value of T in that memory. Box<dyn Trait> is a trait object that allows you to store a value of any type that implements Trait in the heap.
This is called dynamic dispatch because the method to call is determined at runtime, not at compile time. This is in contrast to static dispatch, where the method to call is determined at compile time.
You need to define a function that returns a Box<dyn Speakable> based on a condition.
Here is what you need to do:
Speakable trait with a method speak that returns a String.Dog with two fields: name and breed, both of type String.Speakable trait for Dog to return a string Woof.Robot with two fields: model and purpose, both of type String.Speakable trait for Robot to return a string Beep boop.get_speaker that takes a &str parameter and returns either a Dog or a Robot based on the parameter.dog or robot.pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Dog { fn speak(&self) -> String { String::from("Woof") }}impl Speakable for Robot { fn speak(&self) -> String { String::from("Beep boop") }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog { name: "wtoto".to_string(), breed: "wow".to_string(), }) } "robot" => { // Return a Robot instance here Box::new(Robot { model: "whow".to_string(), purpose:"twe".to_string(), }) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Dog { fn speak(&self) -> String { String::from("Woof") }}impl Speakable for Robot { fn speak(&self) -> String { String::from("Beep boop") }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog { name: "wtoto".to_string(), breed: "wow".to_string(), }) } "robot" => { // Return a Robot instance here Box::new(Robot { model: "whow".to_string(), purpose:"twe".to_string(), }) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}#[derive(Default)]pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_owned() }}#[derive(Default)]pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_owned() } }pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog::default()) } "robot" =>{ // Return a Robot instance here Box::new(Robot::default()) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_owned() }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_owned() } }pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog{name: "".to_string(), breed: "".to_string()}) } "robot" =>{ // Return a Robot instance here Box::new(Robot{model: "".to_string(), purpose: "".to_string()}) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Dog { fn speak(&self) -> String { String::from("Woof") }}impl Speakable for Robot { fn speak(&self) -> String { String::from("Beep boop") }}impl Dog { fn new(name: &str, breed: &str) -> Self { Dog { name: name.to_string(), breed: breed.to_string(), } }}impl Robot { fn new(model: &str, purpose: &str) -> Self { Robot { model: model.to_string(), purpose: purpose.to_string(), } }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => Box::new(Dog::new("Buddy", "Golden Retriever")), "robot" => Box::new(Robot::new("R2-D2", "Astromech")), _ => panic!("Unknown speaker type"), }}pub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak());}pub trait Speakable { fn speak(&self) -> String;}#[derive(Default)]pub struct Dog { pub name: String, pub breed: String,}#[derive(Default)]pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Dog { fn speak(&self) -> String { String::from("Woof") }}impl Speakable for Robot { fn speak(&self) -> String { String::from("Beep boop") }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog::default()) } "robot" => { // Return a Robot instance here Box::new(Robot::default()) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog{name:"test".to_string(), breed:"".to_string()}) } "robot" => { // Return a Robot instance here Box::new(Robot{model:"".to_string(), purpose:"".to_string()}) } _ => panic!("Unknown speaker type"), }}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_string() }}pub struct Robot { pub model: String, pub purpose: String}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_string() }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { String::from("Woof") }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { String::from("Beep boop") }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => Box::new(Dog { name: String::from("Fido"), breed: String::from("Labrador"), }), "robot" => Box::new(Robot { model: String::from("RX-78"), purpose: String::from("Companion"), }), _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub struct Dog{ pub name: String, pub breed: String,}pub struct Robot{ pub model: String, pub purpose: String,}pub trait Speakable { fn speak(&self) -> String ;}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_string() }}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_string() }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { let default_value="unspecified".to_string(); match kind { "dog" => { Box::new(Dog{ name: default_value.clone(), breed: default_value}) }, "robot" => { Box::new(Robot{model: default_value.clone(), purpose: default_value}) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub struct Dog { pub name: String, pub breed: String,}pub struct Robot { pub model: String, pub purpose: String,}pub trait Speakable { fn speak(&self) -> String;}impl Speakable for Dog { fn speak(&self) -> String { "Woof".into() }}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".into() }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => Box::new(Dog { name: "foo".into(), breed: "bar".into(), }), "robot" => Box::new(Robot { model: "foo".into(), purpose: "bar".into(), }), _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => Box::new(Dog { name: "Rex".to_string(), breed: "Pastor Alemão".to_string() }), "robot" => Box::new(Robot { model: "C3PO".to_string(), purpose: "Engineering".to_string() }), _ => panic!("Unknown speaker type"), }}pub struct Dog { pub name: String, pub breed: String,}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_string() }}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_string() }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { String::from("Woof") }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { String::from("Beep boop") }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog { name: String::from("Buddy"), breed: String::from("Golden Retriever"), }) } "robot" => { // Return a Robot instance here Box::new(Robot { model: String::from("XJ-9"), purpose: String::from("Household Assistant"), }) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { String::from("Woof") }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { String::from("Beep boop") }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => Box::new(Dog { name: "Fido".to_string(), breed: "German shepard".to_string(), }), "robot" => Box::new(Robot { model: "X1".to_string(), purpose: "generic".to_string(), }), _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { return "Woof".to_string(); }}pub struct Robot { pub purpose: String, pub model: String,}impl Speakable for Robot { fn speak(&self) -> String { return "Beep boop".to_string(); }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { Box::new(Dog { breed: "".to_string(), name: "".to_string()}) } "robot" => { Box::new(Robot { model: "".to_string(), purpose: "".to_string()}) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { String::from("Woof") }}pub struct Robot { pub model: String, pub purpose: String}impl Speakable for Robot { fn speak(&self) -> String { String::from("Beep boop") }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog { name: String::from("Vendi"), breed: String::from("nive") }) } "robot" => { // Return a Robot instance here Box::new(Robot { model: String::from("boston"), purpose: String::from("cleaning") }) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_string() }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_string() }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => Box::new(Dog { name: "Fater".to_string(), breed: "Border-Collie".to_string(), }), "robot" => Box::new(Robot { model: "XF32".to_string(), purpose: "Refueling".to_string(), }), _ => panic!("Unknown speaker type"), }}pub trait Speakable { fn speak(&self) -> String; }pub struct Dog { pub name: String, pub breed: String}pub struct Robot { pub model: String, pub purpose: String}impl Speakable for Dog { fn speak(&self) -> String { String::from("Woof") }}impl Speakable for Robot { fn speak(&self) -> String { String::from("Beep boop") } }pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog { name: "Tom".into(), breed: "Chiuauha".into() }) } "robot" => { // Return a Robot instance here Box::new(Robot { model: "AI453".into(), purpose: "Terminator".into() }) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { "Woof".into() }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".into() }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => Box::new(Dog { name: "".into(), breed: "".into(), }), "robot" => Box::new(Robot { model: "".into(), purpose: "".into(), }), _ => panic!("Unknown speaker type"), }}#[derive(Default)]pub struct Dog { pub name: String, pub breed: String,}#[derive(Default)]pub struct Robot { pub model: String, pub purpose: String,}pub trait Speakable { fn speak(&self) -> String;}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_string() }}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_string() }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog::default()) } "robot" => { // Return a Robot instance here Box::new(Robot::default()) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}#[derive(Debug, Default)]pub struct Dog { pub name: String, pub breed: String,}#[derive(Debug, Default)]pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Dog { fn speak(&self) -> String { String::from("Woof") }}impl Speakable for Robot { fn speak(&self) -> String { String::from("Beep boop") }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { Box::new(Dog::default()) } "robot" => { Box::new(Robot::default()) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { String::from("Woof") }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { String::from("Beep boop") }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog { name: "Luna".to_string(), breed: "Border collie".to_string() }) } "robot" => { // Return a Robot instance here Box::new(Robot { model: "1A".to_string(), purpose: "Serve coffee".to_string() }) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { String::from("Woof") }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { String::from("Beep boop") }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog { name: String::from("Jojo"), breed: String::from("Pug"), }) } "robot" => { // Return a Robot instance here Box::new(Robot { model: String::from("MIT"), purpose: String::from("Clean"), }) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub struct Dog { pub name: String, pub breed: String}pub trait Speakable { fn speak(&self) -> String;}impl Speakable for Dog{ fn speak(&self)->String{ return String::from("Woof"); }}pub struct Robot { pub model: String, pub purpose: String}impl Speakable for Robot{ fn speak(&self)-> String{ return String::from("Beep boop"); }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here let dog = Box::new(Dog { name:String::from("dog"), breed:String::from("German Shepherd") }); return dog; }, "robot" => { // Return a Robot instance here let robot = Box::new(Robot { model: String::from("latest Model"), purpose: String::from("reduce human work") }); return robot; }, _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_string() }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_string() }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => Box::new(Dog { name: "".to_string(), breed: "".to_string(), }), "robot" => Box::new(Robot { model: "".to_string(), purpose: "".to_string(), }), _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable{ fn speak(&self) -> String;}pub struct Dog {pub name: String, pub breed: String}pub struct Robot {pub model: String, pub purpose: String}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_string() }}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_string() }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog{name: "dong".to_string(), breed: "mix".to_string()}) } "robot" => { // Return a Robot instance here Box::new(Robot{model: "hi".to_string(), purpose: "die".to_string()}) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_string() }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_string() }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => Box::new(Dog { name: "Gigi".to_string(), breed: "Cutest".to_string(), }), "robot" => Box::new(Robot { model: "R2D2".to_string(), purpose: "Lay the law".to_string(), }), _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here return Box::new(Dog{name: String::new(), breed: String::new()}) } "robot" => { // Return a Robot instance here return Box::new(Robot{model: String::new(), purpose: String::new()}) } _ => panic!("Unknown speaker type"), }}pub trait Speakable{ fn speak(&self) -> String;}pub struct Dog{ pub name :String, pub breed :String,}impl Speakable for Dog{ fn speak(&self) -> String{ return String::from("Woof") }}pub struct Robot{ pub model: String, pub purpose: String,}impl Speakable for Robot{ fn speak(&self) -> String{ return String::from("Beep boop") }} // Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable{ fn speak(&self) -> String;}pub struct Dog{ pub name : String, pub breed : String}impl Speakable for Dog{ fn speak(&self)->String{ String::from("Woof") }}pub struct Robot{ pub model : String, pub purpose : String}impl Speakable for Robot{ fn speak(&self) -> String{ String::from("Beep boop") }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here return Box::new(Dog{name: String::new(), breed: String::new()}); } "robot" => { // Return a Robot instance here return Box::new(Robot{model : String::new(), purpose: String::new()}); } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog {name: "a".to_string(), breed: "b".to_string()}) } "robot" => { // Return a Robot instance here Box::new(Robot {model: "a".to_string(), purpose: "b".to_string()}) } _ => panic!("Unknown speaker type"), }}pub trait Speakable { fn speak(&self) -> &'static str;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> &'static str { "Woof" }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> &'static str { "Beep boop" }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_string() }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_string() }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => Box::new(Dog { name: String::from("name"), breed: String::from("breed"), }), "robot" => Box::new(Robot { model: String::from("model"), purpose: String::from("purpose"), }), // Return a Robot instance here _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_string() }}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_string() }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => Box::new(Dog { name: "dog".to_string(), breed: "breed".to_string(), }), "robot" => Box::new(Robot { model: "model".to_string(), purpose: "p".to_string(), }), _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable{ fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String}pub struct Robot { pub model: String, pub purpose: String}impl Speakable for Dog{ fn speak(&self) -> String { String::from("Woof") }}impl Speakable for Robot{ fn speak(&self) -> String { String::from("Beep boop") }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog{ breed: String::from("Golden Retriever"), name: String::from("Dog"), }) } "robot" => { // Return a Robot instance here Box::new(Robot { model: String::from("T-O1"), purpose: String::from("Genocide"), }) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { return "Woof".to_string(); }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { return "Beep boop".to_string(); }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => Box::new(Dog { name: "A".to_string(), breed: "B".to_string(), }), "robot" => Box::new(Robot { model: "A".to_string(), purpose: "B".to_string(), }), _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_string() }}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_string() }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new( Dog { name: "yogi".to_string(), breed: "Chihua-hua".to_string(), } ) } "robot" => { // Return a Robot instance here Box::new( Robot { model: "modern".to_string(), purpose: "allround".to_string(), } ) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self)->String;}pub struct Dog { pub name:String, pub breed:String}impl Speakable for Dog { fn speak(&self)->String { "Woof".to_string() } }pub struct Robot { pub model:String, pub purpose:String}impl Speakable for Robot { fn speak(&self)->String { "Beep boop".to_string() } }pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { Box::new(Dog{name:String::from("raju"),breed:"bye".to_string()}) } "robot" => { // Return a Robot instance here Box::new(Robot{model:String::from("raju"),purpose:"bye".to_string()}) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String}impl Speakable for Dog { fn speak(&self) -> String { String::from("Woof") }}pub struct Robot { pub model: String, pub purpose: String}impl Speakable for Robot { fn speak(&self) -> String { String::from("Beep boop") }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { Box::new(Dog { name: "val".to_string(), breed: "val".to_string() }) } "robot" => { Box::new(Robot { model: "val".to_string(), purpose: "val".to_string() }) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { "Woof".into() }}impl Dog { pub fn new() -> Dog { Dog { name: "".into(), breed: "".into(), } }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".into() }}impl Robot { pub fn new() -> Robot { Robot { model: "".into(), purpose: "".into(), } }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { Box::new(Dog::new()) } "robot" => { Box::new(Robot::new()) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { "Woof".into() }}impl Dog { pub fn new() -> Dog { Dog { name: "".into(), breed: "".into(), } }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".into() }}impl Robot { pub fn new() -> Robot { Robot { model: "".into(), purpose: "".into(), } }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { Box::new(Dog::new()) } "robot" => { Box::new(Robot::new()) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String { "sum".to_string() }}pub struct Dog { pub name: String, pub breed: String,}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_string() } }impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_string() }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new( Dog { name: "name".to_string(), breed: "breed".to_string() } ) } "robot" => { // Return a Robot instance here Box::new(Robot { model: "model".to_string(), purpose: "purpose".to_string(), }) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Dog { fn speak(&self) -> String { String::from("Woof") }}impl Speakable for Robot { fn speak(&self) -> String { String::from("Beep boop") }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog { name: String::from("Dog 1"), breed: String::from("Breed 1") }) } "robot" => { // Return a Robot instance here Box::new(Robot { model: String::from("Dog 1"), purpose: String::from("Breed 1") }) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}#[derive(Default)]pub struct Dog { pub name: String, pub breed: String,}#[derive(Default)]pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_string() }}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_string() }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { Box::new(Dog::default()) } "robot" => { Box::new(Robot::default()) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}#[derive(Default)]pub struct Dog { pub name: String, pub breed: String,}#[derive(Default)]pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_string() }}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_string() }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { Box::new(Dog::default()) } "robot" => { Box::new(Robot::default()) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_string() }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_string() }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { Box::new(Dog{breed:"World".to_string(), name:"Hello".to_string()}) } "robot" => { Box::new(Robot{model: "Hello".to_string(), purpose:"World".to_string()}) } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name : String, pub breed : String}impl Speakable for Dog { fn speak(&self) -> String{ return String::from("Woof"); }}pub struct Robot { pub model : String, pub purpose: String}impl Speakable for Robot { fn speak(&self) -> String { return String::from("Beep boop"); }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here return Box::new(Dog{ name : "Pantufa".to_string(), breed: "cat".to_string()}); } "robot" => { // Return a Robot instance here return Box::new(Robot{model:"android".to_string(), purpose: "play".to_string()}); } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog{ name: "Buddy".to_string(), breed: "German Shepherd".to_string(), }) } "robot" => { Box::new(Robot { model: "Chitti".to_string(), purpose: "Cleaning".to_string(), }) } _ => panic!("Unknown speaker type"), }}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name:String, pub breed:String}impl Speakable for Dog{ fn speak(&self)->String{ return "Woof".to_string(); } }pub struct Robot { pub model:String, pub purpose:String} impl Speakable for Robot{ fn speak(&self)->String{ return "Beep boop".to_string(); } }// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog{ name: "Rex".to_string(), breed: "German Shepherd".to_string(), }) } "robot" => { Box::new(Robot { model: "R2-D2".to_string(), purpose: "Astromech".to_string(), }) } _ => panic!("Unknown speaker type"), }}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name:String, pub breed:String}impl Speakable for Dog{ fn speak(&self)->String{ return "Woof".to_string(); } }pub struct Robot { pub model:String, pub purpose:String} impl Speakable for Robot{ fn speak(&self)->String{ return "Beep boop".to_string(); } }// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { "Woof".to_string() }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { "Beep boop".to_string() }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => Box::new(Dog { name: "shute".to_string(), breed: "special".to_string(), }), "robot" => Box::new(Robot { model: "lite".to_string(), purpose: "help".to_string(), }), _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here Box::new(Dog{name:"aa".to_string(),breed:"bb".to_string()}) } "robot" => { // Return a Robot instance here Box::new(Robot{model:"aa".to_string(),purpose:"bb".to_string()}) } _ => panic!("Unknown speaker type"), }}pub trait Speakable{ fn speak(&self)->String;}pub struct Dog{ pub name : String, pub breed : String}impl Speakable for Dog{ fn speak(&self)->String{ "Woof".to_string() }}pub struct Robot{ pub model : String, pub purpose : String}impl Speakable for Robot{ fn speak(&self) -> String{ "Beep boop".to_string() }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { String::from("Woof") }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { String::from("Beep boop") }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here return Box::new(Dog { name: String::from("Orlando"), breed: String::from("Golden") }); } "robot" => { // Return a Robot instance here return Box::new(Robot{ model: String::from("Thermomix"), purpose: String::from("Cooking") }); } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}pub trait Speakable { fn speak(&self) -> String;}pub struct Dog { pub name: String, pub breed: String,}impl Speakable for Dog { fn speak(&self) -> String { String::from("Woof") }}pub struct Robot { pub model: String, pub purpose: String,}impl Speakable for Robot { fn speak(&self) -> String { String::from("Beep boop") }}pub fn get_speaker(kind: &str) -> Box<dyn Speakable> { match kind { "dog" => { // Return a Dog instance here return Box::new(Dog { name: String::from("Orlando"), breed: String::from("Golden") }); } "robot" => { // Return a Robot instance here return Box::new(Robot{ model: String::from("Thermomix"), purpose: String::from("Cooking") }); } _ => panic!("Unknown speaker type"), }}// Example usagepub fn main() { let dog_speaker = get_speaker("dog"); println!("{}", dog_speaker.speak()); // Expected output: Woof let robot_speaker = get_speaker("robot"); println!("{}", robot_speaker.speak()); // Expected output: Beep boop}