1 A variable was borrowed as mutable more than once.
3 Erroneous code example:
10 // error: cannot borrow `i` as mutable more than once at a time
13 Please note that in Rust, you can either have many immutable references, or one
14 mutable reference. For more details you may want to read the
15 [References & Borrowing][references-and-borrowing] section of the Book.
17 [references-and-borrowing]: https://doc.rust-lang.org/book/ch04-02-references-and-borrowing.html
23 let mut x = &mut i; // ok!
28 let b = &i; // still ok!
29 let c = &i; // still ok!