Example

#[derive(Arbitrary)]
struct A {
    #[arbitrary(with = As::<Option<DisplayFromStr<i32>>>::arbitrary)]
    n: Option<String>,
};

let a: A = u.arbitrary()?;
if let Some(n) = a.n {
    let _i: i32 = n.parse().unwrap();
}

arbitrary_with

serde_with analog for arbitrary