Hands-On Concurrency with Rust

Cell and RefCell

So far in this chapter, the mutable references we've been discussing have a property called, by Rust, inherited mutability. That is, values are made mutable when we inherit their ownership or the exclusive right—via a &mut—to mutate the value. Inherited mutability is preferred in Rust as it is statically enforcable—any defects in our program with regards to memory mutation will be caught at compilation time. Rust does provide facilities for interior mutability,  that being mutability that is available for pieces of an immutable type. The documentation calls interior mutability something of a last resort but, while not common, it is not exactly rare in practice, either. The two options for interior mutability in Rust are ...