Refcell in rust

RefCell And Cell Basically the same , The difference lies in RefCell When reading content , The return is the reference , It's essentially a pointer . This is because RefCell The data to be packaged is not implemented Copy characteristic . The code example is as follows ：

use std::cell::{
    Ref, RefCell};
fn main() {
    
    let x = RefCell::new("good".to_string());
    let a = &x;
    let b = &x;
    *a.borrow_mut() = "nice".to_string();
    *b.borrow_mut() = "best".to_string();
    let y: Ref<String> = x.borrow();
    println!("x = {:?}", x);
    println!("y = {:?}", y);
}
---------------------------------------------------
>cargo run
x = RefCell {
     value: "best" }
y = "best"

rust This set of tools is really beautiful ！