pub struct NewsArticle {
    pub headline: String,
    pub location: String,
    pub author: String,
    pub content: String,
}

impl Summarizable for NewsArticle {
    fn summary(&self) -> String {
        format!("{}, by {} ({})", self.headline, self.author, self.location)
    }
}

pub struct Tweet {
    pub username: String,
    pub content: String,
    pub reply: bool,
    pub retweet: bool,
}

impl Summarizable for Tweet {
    fn summary(&self) -> String {
        format!("{}: {}", self.username, self.content)
    }
}

trait Test1 {
    fn open(&mut self);
}

struct Teststr1{ 
x1: bool,
}

impl Test1 for Teststr1{

  fn open(&mut self) {
    self.x1 = true;
    println!("{}", self.x1);
  }
}



fn main()
{
let mut s1 = Teststr1{x1: false};

s1.open();
}