Rust doesn't have a syntax distinction for passing by reference vs passing by value (which may sound terrible to a C++ programmer, but Rust has no copy construc

Rust doesn't have a syntax distinction for passing by reference vs passing by value (which may sound terrible to a C++ programmer, but Rust has no copy constructors, and types are non-copyable by default, so nothing expensive gets copied by surprise). For example, in the C sense, `Box<u8>` is a pointer, and `&str` is a struct passed by value. Rust is all about ownership, and `&` means "don't free() this".