trait GetPossibleRef<'a> {
    type Result;
    fn get_data(&'a self) -> Self::Result;
}

struct Base(f32);

impl<'a> GetPossibleRef<'a> for Base {
    type Result = &'a f32;
    fn get_data(&'a self) -> Self::Result {
        &self.0
    }
}

fn main() {
    let x = Base(42.3);
    let b: Box<dyn GetPossibleRef<Result = &f32>> = Box::new(x);

    println!("{:?}", b.get_data());
}