vlib/v/checker/tests/sort_method_called_on_immutable_receiver.vv:2:2: error: `a` is immutable, declare it with `mut` to make it mutable
    1 | fn abc (a []int) {
    2 |     a.sort()
      |     ^
    3 | }
    4 |
vlib/v/checker/tests/sort_method_called_on_immutable_receiver.vv:7:2: error: `a` is immutable, declare it with `mut` to make it mutable
    5 | fn main() {
    6 |     a := [2,30,10,20,1]
    7 |     a.sort(a>b)
      |     ^
    8 |     eprintln(' a: $a')
    9 | }
