Rust Default::default()

default_params.rs

use std::fmt; 

struct ApiUrl<'a> {
    host: &'a str,
    port: &'a str,
    path: &'a str,
}

impl Default for ApiUrl<'_> {
    fn default() -> Self {
        ApiUrl {
            host: "http://example.com",
            port: "8000",
            path: "/",
        }
    }
}

impl fmt::Display for ApiUrl<'_> {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        write!(f, "{}:{}{}", self.host, self.port, self.path)
    }
}

fn main() {
    let mut request: ApiUrl = Default::default();
    request.path = "/login";
    
    println!("URL {}", request);
}