clone

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

I have base-class Base from which is derived Derived1 , Derived2 and Derived3 . I have constructed an instance for one of the the derived classes which I store as Base* a . I now need to make a deep copy of the object which I will store as Base* b . As far as I know, the normal way of copying a class is to use copy constructors and to overload operator= . However since I don't know whether a is of type Derived1 , Derived2 or Derived3 , I cannot think of a way of using either the copy constructor or operator= . The only way I can think of to cleanly make this work is to implement something like

So are NFC tags really UNIQUE from each other, at least in their SERIAL NUMBER ? And can we rely on the fact that no 2 NFC tags can have the same serial number? I'm highly skeptical about this as there are (and will be more) NFC tags out there and I don't think anyone is controlling the serials... The reason I'm asking is that I'm developing a key based system using NFC tags. I don't need to write to the tags, I basically just need their serial numbers. But I need them to be truly unique . Also, I would like to know if the serial numbers can be cloned (I know the content of tags can always be

I was looking to find the difference between these four on Google and I expected there to be a huge amount of information on this, but there really wasn't any solid comparison between the four calls. I set about trying to compile a kind of basic at-a-glance look at the differences between these system calls and here's what I got. Is all this information correct/am I missing anything important ? Fork : The fork call basically makes a duplicate of the current process, identical in almost every way (not everything is copied over, for example, resource limits in some implementations but the idea

I am looking for some tips on how to solve my problem. I have a html element (like select box input field) in a table. Now I want to copy the object and generate a new one out of the copy, and that with JavaScript or jQuery. I think this should work somehow but I'm a little bit clueless at the moment. Something like this (pseudo code): oldDdl = $("#ddl_1").get(); newDdl = oldDdl; oldDdl.attr('id', newId); oldDdl.html(); Boris Guéry Using your code you can do something like this in plain JavaScript using the cloneNode() method: // Create a clone of element with id ddl_1: let clone = document