How to convert enum discriminant to trait objects

convetion.rs

use std::fmt::Display;


enum Storage {
    Number(u32),
    Text(String),
}

struct Data {
    storage: Storage
}

impl Data {

    fn new() -> Self {
        Self {
            storage: Storage::Number(0)
        }
    }

    fn get_display(&mut self, a: bool) -> &dyn Display {
        if a==true {
            self.storage = Storage::Number(42_u32);
            if let Storage::Number(ref number) = &mut self.storage {
                number
            } else {
                unreachable!()
            }
        } else {
            self.storage = Storage::Text(String::from("This is a string"));
            if let Storage::Text(ref text) = &mut self.storage {
                text
            } else {
                unreachable!()    
            }
            
        } 
    }
}

fn print(some_value: &dyn Display) {
    println!("{}", some_value )
}


fn main() {
    
    let mut data: Data =  Data::new();
    
    let response: &dyn Display = data.get_display(false);
    
    print(response);
}

See also:
On-Stack Dynamic Dispatch
trait-object