How to program in Rust as if it was old school C++ with pointers

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How to program in Rust as if it was old school C++ with pointers

Basically wrap your data struct in Option<Rc<RefCell<_>>> Better yet, use your custom type that provides few helper functions that make using it as nice as old C++ pointers. Obviously there's no pointer arithmetic, but it works great for dynamically allocated structures like trees or linked lists. Please comment how it's a horrible idea that will bring doom to me and my family. fn main() { struct Data { pub number: i32 } // struct Data { int number; }; let mut p:Pointer<Data> = Pointer(None); // Data *p = NULL; println!("{}", p.is_none()); // printf(p == NULL ? "true\n" : "false\n"); p = Pointer::new(Data { number: 5 }); // p = new Data { number: 5 }; println!("{}", p.pointed().number); // printf("%d\n", p->number); let q = p.clone(); // auto q = p; q.pointed().number = 6; // q->number = 6; println!("{}", p.pointed().number); // printf("%d\n", p->number); println!("{}", p.is_clone_of(&q)); // printf(p == q ? "true\n" : "false\n"); } // delete p; Helper Pointer<T> type: use std::{rc::Rc, cell::{RefCell, RefMut}}; #[derive(Debug)] struct Pointer<T>(Option<Rc<RefCell<T>>>); impl<T> Clone for Pointer<T> { fn clone(&self) -> Self { Pointer(Some(self.0.as_ref().unwrap().clone())) } } impl<T> Pointer<T> { pub fn new(d: T) -> Pointer<T> { Pointer(Some(Rc::new(RefCell::new(d)))) } pub fn pointed(&self) -> RefMut<T> { let res = self.0.as_ref().unwrap().as_ref().borrow_mut(); res } pub fn is_clone_of(&self, other:&Pointer<T>) -> bool { Rc::ptr_eq(&self.0.as_ref().unwrap(), &other.0.as_ref().unwrap()) } pub fn is_none(&self) -> bool { self.0.is_none() } } Live version (Rust): https://play.rust-lang.org/?gist=f43ce73b89537e0a9ae0586169b... Live version (C++): http://tpcg.io/_LNG59M