cloneable

I wrote a program that has the trait Animal and the struct Dog implementing the trait. It also has a struct AnimalHouse storing an animal as a trait object Box<Animal> . trait Animal { fn speak(&self); } struct Dog { name: String, } impl Dog { fn new(name: &str) -> Dog { return Dog { name: name.to_string(), }; } } impl Animal for Dog { fn speak(&self) { println!{"{}: ruff, ruff!", self.name}; } } struct AnimalHouse { animal: Box<Animal>, } fn main() { let house = AnimalHouse { animal: Box::new(Dog::new("Bobby")), }; house.animal.speak(); } It returns "Bobby: ruff, ruff!" as expected, but if I

Can you explain to me why I should inherit from ICloneable and implement the Clone() method? If I want to do a deep copy, can't I just implement my method? Let's say MyClone() ? Why should I inherit from ICloneable ? What are the advantages? Is it just a matter of making code "more readable"? Matt Hamilton You shouldn't. Microsoft recommends against implementing ICloneable because there's no clear indication from the interface whether your Clone method performs a "deep" or "shallow" clone. See this blog post from Brad Abrams back in 2003(!) for more information. supercat The ICloneable

The following compiles fine: Object o = new Object(); System.out.println(o instanceof Cloneable); But this doesn't: String s = new String(); System.out.println(s instanceof Cloneable); A compiler error is thrown. What is the problem? A more blatant incarnation of your problem is the following: if ("foo" instanceof Number) // "Incompatible conditional operand types String and Number" This is specified in JLS 15.20.2 Type comparison operator instanceof : RelationalExpression: RelationalExpression instanceof ReferenceType If a cast of the RelationalExpression to the ReferenceType would be