Rust

Create bindings and print a formatted message.

fn main() {
    let name = "Mira";
    let score = 128;

    println!("{name}: {score} points");
}

Filter even values, square them, and calculate the sum.

fn main() {
    let values = [1, 2, 3, 4, 5, 6];

    let total: i32 = values
        .iter()
        .filter(|value| **value % 2 == 0)
        .map(|value| value * value)
        .sum();

    println!("{total}");
}

Parse a number and propagate a readable error.

fn parse_count(input: &str) -> Result<u32, String> {
    input
        .trim()
        .parse::<u32>()
        .map_err(|error| format!("invalid count: {error}"))
}

fn main() -> Result<(), String> {
    let count = parse_count("42")?;
    println!("{count}");
    Ok(())
}