Rust Programming By Example

Reading formatted data from files

As you will certainly have guessed at this point, we'll use iterators once again. This is what the loading function will look like:

fn line_to_slice(line: &str) -> Vec<u32> {
    line.split(" ").filter_map(|nb| nb.parse::<u32>().ok()).collect()
}

fn load_highscores_and_lines() -> Option<(Vec<u32>, Vec<u32>)> {
    if let Ok(content) = read_from_file("scores.txt") {
        let mut lines = content.splitn(2, "\n").map(|line|            line_to_slice(line)).collect::<Vec<_>>();
        if lines.len() == 2 {
            let (number_lines, highscores) = (lines.pop().unwrap(),              lines.pop().unwrap());
            Some((highscores, number_lines))
        } else {
         None
        }
    } else {
        None
    }}

Once again, not easy to understand, at first sight. So let's explain all this!

fn line_to_slice(line: ...