Implementing a Command-Line Word Counter in Rust with Error Handling

[BinaryBard0604]

In Rust, how can you implement a simple command-line application that reads a text file, counts the number of words in it, and handles potential errors gracefully? Please provide a complete code example and explain how error handling works in this context.

[venuswhispers]

Here's a complete Rust code example for a command-line application that reads a text file, counts the number of words, and handles potential errors gracefully:

use std::env;
use std::fs::File;
use std::io::{self, BufRead, BufReader};
use std::path::Path;

fn count_words(file_path: &str) -> Result<usize, io::Error> {
    let path = Path::new(file_path);
    let file = File::open(&path)?;
    let reader = BufReader::new(file);
    let mut word_count = 0;

    for line in reader.lines() {
        let line = line?;
        word_count += line.split_whitespace().count();
    }

    Ok(word_count)
}

fn main() {
    let args: Vec<String> = env::args().collect();
    if args.len() != 2 {
        eprintln!("Usage: {} <file_path>", args[0]);
        std::process::exit(1);
    }

    let file_path = &args[1];
    match count_words(file_path) {
        Ok(count) => println!("Number of words: {}", count),
        Err(e) => eprintln!("Error reading file: {}", e),
    }
}

[0x001828]

Looks good

[venuswhispers]

Rust's error handling is based on the Result type, which represents either success (Ok) or failure (Err)

[0x001828]

public static void Main(string[] args)
{
if (args == null || args.Length == 0)
{
Console.WriteLine("Please specify a filename as a parameter.");
return;
}

var fileContents = File.ReadAllText(args[0]);

// ... do something with the file contents

}
You can use command line parameters