1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
|
pub struct Something;
type Validator<'a> = dyn 'a + Send + Sync + Fn(&'a Something) -> Result<(), ()>;
pub static ALL_VALIDATORS: &[(&'static str, &'static Validator)] =
&[("validate that credits and debits balance", &validate_something)];
fn or<'a>(first: &'static Validator<'a>, second: &'static Validator<'a>) -> Validator<'a> {
//~^ ERROR return type cannot have an unboxed trait object
return Box::new(move |something: &'_ Something| -> Result<(), ()> {
first(something).or_else(|_| second(something))
});
}
fn validate_something(_: &Something) -> Result<(), ()> {
Ok(())
}
fn main() {}
|