ref: ea3250341f4e4d02b0613be9fc228fac0f4c0e40
dir: /test/genericret.myr/
use std
type t(@a) = union
`Val @a
`None
;;
const f = {-> t(int)
-> `None
}
const main = {
match f()
| `None: std.exit(42)
| _: std.die("Impossible match failure\n");
;;
std.exit(0)
}