vlib/v/checker/tests/for_in_invalid_identifier.vv:2:26: error: undefined ident: `s`
    1 | fn main() {
    2 |     for index, mut value in s.statements {
      |                             ^
    3 |         println('Hello $index $value')
    4 |     }
vlib/v/checker/tests/for_in_invalid_identifier.vv:3:26: error: no known default format for type `void`
    1 | fn main() {
    2 |     for index, mut value in s.statements {
    3 |         println('Hello $index $value')
      |                                ~~~~~
    4 |     }
    5 | }