| // Here we check that it is allowed to lend out an element of a |
| // (locally rooted) mutable, unique vector, and that we then prevent |
| // modifications to the contents. |
| |
| fn takes_imm_elt<F>(_v: &isize, f: F) where F: FnOnce() { |
| f(); |
| } |
| |
| fn has_mut_vec_and_does_not_try_to_change_it() { |
| let mut v: Vec<isize> = vec![1, 2, 3]; |
| takes_imm_elt(&v[0], || {}) |
| } |
| |
| fn has_mut_vec_but_tries_to_change_it() { |
| let mut v: Vec<isize> = vec![1, 2, 3]; |
| takes_imm_elt( |
| &v[0], |
| || { //~ ERROR cannot borrow `v` as mutable |
| v[1] = 4; |
| }) |
| } |
| |
| fn main() { |
| } |
