Golang (may contain syntax errors):
func readNumberFromFileAndDoubleIt(filename string) (int, err) {
file, err = os.Open(filename)
if err != nil {
return 0, err
}
defer file.Close() // BUG!! this returns an error, but since we defer it, it is not going to be handled
bytes, err := ioutil.ReadFile(filename)
if err != nil {
return 0, err
}
contents := string(bytes)
i, err := strconv.Atoi(contents)
if err != nil {
return 0, err
}
return 2*i, nil
}
Rust (may contain syntax errors):
fn read_number_from_file_and_double_it(filename: &str) -> Result<i32> {
let mut file = File::open(filename)?; // file automatically closed at end of scope
let mut contents = String::new();
file.read_to_string(&mut contents)?;
contents.parse().map(|i| 2*i)
}
4 vs 15 lines, I think it's obvious which one is easier to read
