relations-between-regions-v0

fn main() {
  let mut x: i32 = 17;
  let     y: i32 = 21;

  let mut u: Vec<&/* '0 */ i32> = vec![];
  let mut v: Vec<&/* '1 */ i32> = vec![];

  /* { // NLL */

  let p: &/* '3 */ i32 = &/* '2 */x;
  let q: &/* '5 */ i32 = &/* '4 */y;

  let mut r: &/* '6 */ mut Vec<&/* '7 */ i32>;

  r = &/* '8 */ mut u;
  r.push(p);

  r = &/* '9 */ mut v;
  r.push(q);

  /* } // NLL */

  x += 1; // <-- Error! can't mutate `x` while borrowed by `u` through `p`
          // If `'0 == '1 == '7`, could the analysis (wrongly) conclude
          // that the borrowing by `v` is also problematic?

  take(v);
}

fn take<T>(p: T) { /* ... */ }