public/subjects/handling/README.md

handling

Instructions

Write a function, called open_or_create that as two arguments:

• file : &str which is the name of the files
• content: &str being the content to be written into the file

This functions should try to open a file, if it does not exist creates it. You should panic, with the error, in case something goes wrong.

Expected Function

pub fn open_or_create(s: &str, content: &str) {}

Usage

Here is a program to test your function

fn main() {
    let path = "a.txt";
    File::create(path).unwrap();
    open_or_create(path, "content to be written");

    let mut file = File::open(path).unwrap();

    let mut s = String::new();
    file.read_to_string(&mut s).unwrap();
    println!("{}", s);
}

And its output:

student@ubuntu:~/[[ROOT]]/test$ cargo run
content to be written
student@ubuntu:~/[[ROOT]]/test$

Notions

• https://doc.rust-lang.org/std/io/enum.ErrorKind.html
• https://doc.rust-lang.org/std/fs/struct.File.html