Using Cow in Rust for efficient memory utilization

Clone-on-write (Cow) in Rust is a mechanism that provides optional ownership, optimizing memory usage and performance for cases where data duplication is costly and modification is infrequent. It is particularly useful when dealing with large data structures like vectors or strings, allowing developers to avoid unnecessary memory allocation by either borrowing values or owning them only when needed. The Cow type is built on Rust's enums and traits, enabling a flexible system where Cow can either borrow a reference or own a value, depending on the presence of duplicates or the need for modification. This approach is beneficial when read-only access is predominant, and it aligns with similar memory optimization techniques, such as Linux's copy-on-write for process forking. The use of Cow can simplify code maintenance and improve efficiency by reducing the overhead involved in copying large data structures unnecessarily.