#[derive(Debug)]
struct MyError(String);

impl<T> From<T> for MyError
    where T: ToString,
{
    fn from(s: T) -> Self {
        Self(s.to_string())
    }
}

impl std::fmt::Display for MyError {
    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
        write!(f, "{}", self.0)
    }
}

fn main() {
    let a: MyError = 2.into();
    let b: MyError = "Hey".into();
    println!("{:?}, {:?}", a, b);
}