Error-handling with try!

In the same way as we did for reading a file, we could also use the try! macro when writing to a file, like here:

// code from Chapter 11/code/write_file_try.rs: 
use std::path::Path; 
use std::fs::File; 
use std::io::prelude::*; 
use std::error::Error; 
use std::io; 
 
struct Info { 
    name: String, 
    age: i32, 
    rating: i32 
} 
 
impl Info { 
    fn as_bytes(&self) -> &[u8] { 
        self.name.as_bytes() 
    } 
 
    fn format(&self) -> String { 
        format!("{};{};{}\n", self.name, self.age, self.rating)  
    } 
} 
 
fn main() { 
    let path = Path::new("info.txt"); 
    let display = path.display(); 
 
    let file = match write_file(&path) { 
        Err(why) => panic!("couldn't write info to file {}: {}", 
                           display, 
                           Error::description(&why)), 
        Ok(file) => file, 
    }; 
} 
 
fn write_file(path: &Path) -> Result<File, io::Error> {    let mut file = try!(File::create(path)); 
    let info1 = Info { name:"Barak".to_string(), age: 56, rating: 8 }; 
    let info2 = Info { name:"Vladimir".to_string(), age: 55, rating: 6 }; 
    try!(file.write(info1.as_bytes()));    
    try!(file.write(b"\r\n"));    
    try!(file.write(info2.as_bytes())); 
    Ok(file) 
} 

To open a file in other modes, use the OpenOptions struct from std::fs.