use std::convert::{TryFrom, TryInto};
use num_traits::cast::AsPrimitive;

struct Numeric(u64);

enum SomeType {
  Numeric(Numeric),
}

impl<T: Into<u64>> From<T> for SomeType {
    fn from(n: T) -> Self {
        SomeType::Numeric(Numeric(n.into()))
    }
}
fn main() {
    let x: SomeType = 0u8.try_into().unwrap();
}