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0 pointscomex1y ago0 comments

Only problem is that the critical `chars` method doesn't actually exist. Rust's standard library has a `chars` method for strings, but not for Readers.

(Also, the comment about the iterator element type is inconsistent with the code following it. Based on the comment, `c` would be of type `(char, usize)`, but then trying to print it with {} would fail because tuples don't implement Display.)

0 comments

raggi1y ago

good catch. feeding it the error output of rustc it then produces:

    use std::fs::File;
    use std::io::{self, Read};

    fn read_file_character_by_character(path: &str) -> io::Result<()> {
        let mut file = File::open(path)?;
        let mut contents = String::new();

        file.read_to_string(&mut contents)?;

        for c in contents.chars() {
            println!("{}", c);
        }

        Ok(())
    }

    fn main() {
        let path = "path/to/your/file.txt";

        if let Err(e) = read_file_character_by_character(path) {
            eprintln!("Error reading file: {}", e);
        }
    }

phaer1y ago

But this doesn't read the file char-by-char, but uses buffering to read it into a string

scottlamb1y ago

What would you expect? There's no OS API for "read one character", except in say ASCII where 1 byte = 1 code point = 1 character. And it'd be hideously inefficient anyway. So you either loop over getting the next N bytes and getting all complete characters so far (with some extra complexity around characters that cross chunk boundaries) or you read the whole thing into a single buffer and iterate the characters. This code does the latter. If this tool doesn't have the ability to respond by asking requirements questions, I'd consider either choice valid.

Of course, in real life, I do expect to get requirements questions back from an engineer when I assign a task. Seems more practical than anticipating everything up-front into the perfect specification/prompt. Why shouldn't I expect the same from an LLM-based tool? Are any of them set up to do that?

1 more reply

1letterunixname1y ago

A few notes:

- It should be generating `path: impl AsRef<Path>` to be properly generic.

- It's not setting a nonzero exit code on error.

- Edge case handling is a vital property for production-usable tools at scale. I'm wondering if it can yet special case situations such as creating a conditional compilation version for Linux that uses the splice syscall when the arguments are 2 file handles.

deathanatos1y ago

On errors, it exits with success.

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