using rust default value

Rust Default::default is really useful to place default value to a structure or pass it into a function. 

Example below shows how we use the .. operator to assigned default value to more than one fields, when we instantiate the struct / type Point. 

#[derive(Debug, Default)]

struct Point {

    x: i32,

    y: i32,

    a: i32,

    isOk: bool

}

fn main() {

   let s = Point {

     isOk: true,

     ..Default::default()

   };

   

   println!("{:?}", s);

}

 You can also use that to pass function - for example and it prints out 0 as the total. 

fn print_value(total: u32)

{

    print!("{}", total);

}

fn main() {

    print_value(Default::default())

   

}