error[E0596]: cannot borrow `*x` as mutable, as it is behind a `&` reference --> $DIR/slice-mut-2.rs:7:18 | LL | let x: &[isize] = &[1, 2, 3, 4, 5]; | ---------------- help: consider changing this to be a mutable reference: `&mut [1, 2, 3, 4, 5]` ... LL | let _ = &mut x[2..4]; //~ERROR cannot borrow immutable borrowed content `*x` as mutable | ^ `x` is a `&` reference, so the data it refers to cannot be borrowed as mutable error: aborting due to previous error For more information about this error, try `rustc --explain E0596`.