// Test mutability and slicing syntax. fn main() { let x: &[isize] = &[1, 2, 3, 4, 5]; // Can't mutably slice an immutable slice let slice: &mut [isize] = &mut [0, 1]; let _ = &mut x[2..4]; //~ERROR cannot borrow `*x` as mutable, as it is behind a `&` reference }