rustdatastructurestructprintdisplay.success.rs

use std::fmt::{self, Formatter, Display};

/*
    Specify that structure implements the Debug trait
    i.e. we will be able to print structure contents by using {:?} specifier in our print statements
*/
//#[derive(Debug)]

struct Person 
{
      name: String
    , age: u8
}


/*
    Rust - How to print structs and arrays?
    https://stackoverflow.com/questions/30253422/how-to-print-structs-and-arrays
    
    All types can derive (automatically create) the fmt::Debug implementation as #[derive(Debug)], 
    but fmt::Display must be manually implemented.

    You can create a custom output:

*/
impl std::fmt::Display for Person 
{

    fn fmt
    (
        &self, f: &mut std::fmt::Formatter
    ) -> std::fmt::Result 
    {
    
        write!
            (
                  f
                , "Person ( name: \"{0}\",  age: {1} )"
                , self.name
                , self.age
            )
    }

    
}


fn main() 
{

    // Create struct with field init shorthand
    
    //String Literals ( static )
    let nameHardCoded:&'static str = "Peter 1";
    
    let age = 27;
    
    let objPeter = Person 
                    { 
                          name:nameHardCoded.to_string()
                        , age:age
                    };
    

    //Debug Basic Print Person 1
    println!
    (
          "{0}"
        , objPeter
    );
   

    //String Literals ( static )
    let nameJohn = "John 2";
    let objJohn = nameJohn.to_string();
    
    let ageJohn = 29;
    
  
    let objJohn = Person 
                    { 
                          name:objJohn
                        , age:ageJohn
                    };
    

    //Debug Basic Print Person 1
    println!
    (
          "{0}"
        , objJohn
    );
 
  
}