Rust Code Snippets

When dealing with directories and files it may be necessary to check for their existence. Below is an example of how to do this.

use std::path::Path;

fn main() {

    // Example directory and file.
    let example_directory = "C:\\demo\\";
    let example_file = "C:\\demo\\demo.txt";

    // Check if the directory exists.
    if Path::new(example_directory).is_dir()
    {
        println!("The directory '{}' exists.", example_directory);   
    }
    else
    {
        println!("The directory '{}' doesn't exist.", example_directory);  
    }

    // Check if the file exists.
    if Path::new(example_file).is_file()
    {
        println!("The file '{}' exists.", example_file);
    }
    else
    {
        println!("The file '{}' doesn't exist.", example_file);
    }

}

Here is an example of how to generate a random number between two values, in this case 1 and 59, then display it.

use rand::Rng;

fn main() {

    // Minimum and maximum values for random number.
    let min_val = 1;
    let max_val = 59;

    // Generate random number.
    let mut rng = rand::thread_rng();
    let random_number = rng.gen_range(min_val..max_val+1);

    // Display the result in the console or terminal.
    println!("{}", random_number);

}

A text file can be read from and processed line by line.

use std::fs::File;
use std::io::{BufRead, BufReader};

fn main() {

    // Open file and assign it to a reader object.
    let file = File::open("C:\\demo\\demo.txt").unwrap();
    let reader = BufReader::new(file);

    // Process the lines in the file.
    for line in reader.lines()
    {
        // Display the line in the console/terminal.
        println!("{}", line.unwrap());
    }

}