Here's a static check Rust's Box<T> offers over C++'s std::unique_ptr<T>. The following program is obviously incorrect to someone familiar with smart pointers.

Here's a static check Rust's Box<T> offers over C++'s std::unique_ptr<T>. The following program is obviously incorrect to someone familiar with smart pointers. The code compiles without error, and the program crashes as expected. % cat demo.cpp #include <iostream> #include <memory> int main() { std::unique_ptr<std::string> foo = std::make_unique<std::string>("bar"); std::unique_ptr<std::string> bar = std::move(foo); std::cout << *foo << *bar << std::endl; } % clang -std=c++2b -lstdc++ -Weverything demo.cpp warning: include location '/usr/local/include' is unsafe for cross-compilation [-Wpoison-system-directories] 1 warning generated. % ./a.out zsh: segmentation fault ./a.out The equivalent Rust code fails to compile. % cat demo.rs fn main() { let foo = Box::new("bar"); let bar = foo; println!("{foo} {bar}") } % rustc demo.rs error[E0382]: borrow of moved value: `foo` --> demo.rs:5:13 | 2 | let foo = Box::new("bar"); | --- move occurs because `foo` has type `Box<&str>`, which does not implement the `Copy` trait 3 | let bar = foo; | --- value moved here 4 | 5 | println!("{foo} {bar}") | ^^^^^ value borrowed here after move help: consider cloning the value if the performance cost is acceptable | 3 | let bar = foo.clone(); | ++++++++ Not only does Rust emit an error, but it even suggests a fix for the error.