C++'s const has some issues, so I can see why. Plus, it's possible to design around it by means of immutable data structures (e.g. see Scala). I think that Rus

C++'s const has some issues, so I can see why. Plus, it's possible to design around it by means of immutable data structures (e.g. see Scala). I think that Rust's approach is superior to C++'s here, but even that has some issues so they have to retort to interior mutability via RefCell.