vlib/v/checker/tests/compile_error_call_position.vv:3:11: notice: unused parameter: `val`
    1 | module main
    2 | 
    3 | fn son[T](val T) {
      |           ~~~
    4 |     $if T !is int {
    5 |         $compile_error('son only taken int as input')
vlib/v/checker/tests/compile_error_call_position.vv:10:2: error: son only taken int as input
    8 | 
    9 | fn main() {
   10 |     son(false)
      |     ~~~~~~~~~~
   11 | }