tests/ui/borrowck/borrowck-slice-pattern-element-loan-array-no-overlap.rs

   1 // check-pass
   2
   3 fn nop(_s: &[& i32]) {}
   4 fn nop_subslice(_s: &[i32]) {}
   5
   6 fn const_index_ok(s: &mut [i32; 4]) {
   7     let [ref first, ref second, _, ref fourth, ..] = *s;
   8     let [_, _, ref mut third, ..] = *s;
   9     nop(&[first, second, third, fourth]);
  10 }
  11
  12 fn const_index_from_end_ok(s: &mut [i32; 4]) {
  13     let [.., ref fourth, ref third, _, ref first] = *s;
  14     let [.., ref mut second, _] = *s;
  15     nop(&[first, second, third, fourth]);
  16 }
  17
  18 fn const_index_mixed(s: &mut [i32; 6]) {
  19     let [.., _, ref from_end4, ref from_end3, _, ref from_end1] = *s;
  20
  21     let [ref mut from_begin0, ..] = *s;
  22     nop(&[from_begin0, from_end1, from_end3, from_end4]);
  23     let [_, ref mut from_begin1, ..] = *s;
  24     nop(&[from_begin1, from_end1, from_end3, from_end4]);
  25
  26     let [ref from_begin0, ref from_begin1, _, ref from_begin3, _, ..] = *s;
  27
  28     let [.., ref mut from_end1] = *s;
  29     nop(&[from_begin0, from_begin1, from_begin3, from_end1]);
  30     let [.., ref mut from_end2, _] = *s;
  31     nop(&[from_begin0, from_begin1, from_begin3, from_end2]);
  32     let [.., ref mut from_end4, _, _, _] = *s;
  33     nop(&[from_begin0, from_begin1, from_begin3, from_end4]);
  34 }
  35
  36 fn const_index_and_subslice_ok(s: &mut [i32; 4]) {
  37     let [ref first, ref second, ..] = *s;
  38     let [_, _, ref mut tail @ ..] = *s;
  39     nop(&[first, second]);
  40     nop_subslice(tail);
  41 }
  42
  43 fn const_index_and_subslice_from_end_ok(s: &mut [i32; 4]) {
  44     let [.., ref second, ref first] = *s;
  45     let [ref mut tail @ .., _, _] = *s;
  46     nop(&[first, second]);
  47     nop_subslice(tail);
  48 }
  49
  50 fn subslices(s: &mut [i32; 4]) {
  51     let [_, _, ref s1 @ ..] = *s;
  52     let [ref mut s2 @ .., _, _] = *s;
  53     nop_subslice(s1);
  54     nop_subslice(s2);
  55 }
  56
  57 fn main() {
  58     let mut v = [1,2,3,4];
  59     const_index_ok(&mut v);
  60     const_index_from_end_ok(&mut v);
  61     const_index_and_subslice_ok(&mut v);
  62     const_index_and_subslice_from_end_ok(&mut v);
  63     subslices(&mut v);
  64 }