rust - 如何使用 `read_line()` 检查 EOF？

Question

给出下面的代码，我如何专门检查 EOF？或者更确切地说，我如何区分“这里什么都没有”和“它爆炸了”？

match io::stdin().read_line() {
    Ok(l) => print!("{}", l),
    Err(_) => do_something_else(),
}

Answer 1

来自documentation for read_line :

If successful, this function will return the total number of bytes read.

If this function returns Ok(0), the stream has reached EOF.

这意味着我们可以检查成功的零值:

use std::io::{self, BufRead};

fn main() -> io::Result<()> {
    let mut empty: &[u8] = &[];
    let mut buffer = String::new();

    let bytes = empty.read_line(&mut buffer)?;
    if bytes == 0 {
        println!("EOF reached");
    }

    Ok(())
}