6.11 Summary

Rust’s ownership system breaks from traditional memory management in C but does so without sacrificing performance:

  • Ownership and Move Semantics: Each piece of data has a single owner, and transferring ownership (“move”) avoids double frees or invalid pointers.
  • Cloning vs. Copying: Rust distinguishes between explicit .clone() for deep copies and inexpensive bitwise copies for simple stack-based types.
  • Borrowing and References: References provide non-owning access to data under rules that eliminate data races.
  • Lifetimes: Guarantee references never outlive the data they point to, preventing dangling pointers.
  • Slices: Borrow contiguous segments of arrays or strings without extra allocations.
  • Smart Pointers: Types like Box<T>, Rc<T>, Arc<T>, and RefCell<T> offer additional ways to manage heap data and shared references.
  • Unsafe Rust: Allows low-level control in well-defined unsafe blocks.
  • C Interoperability: Rust can directly call C (and vice versa), making it a strong candidate for systems-level work.
  • Comparison with C Memory Management: Rust’s rules and compile-time checks eliminate many of the memory and concurrency pitfalls that are common in C.

By mastering ownership, borrowing, and lifetimes, you will write safer, more robust, and highly performant programs—free from the overhead of a traditional garbage collector.