Educational implementation of the echo command in Rust.

echo.rs

pub fn main() {
    // collect the command line arguments into a vector of string
    let argv: Vec<String> = std::env::args().collect();

    // iterate over the vector of args ignoring the first argument
    for arg in &argv[1..] {
        // ignore args starting with '-'
        if !arg.starts_with("-") {
            // print argument without newline
            print!(
                "{} ",
                arg
                    // replace escape sequences with their hex code
                    .replace("\\b", "\x08")
                    .replace("\\t", "\x09")
                    .replace("\\n", "\x0a")
                    .replace("\\v", "\x0b")
                    .replace("\\f", "\x0c")
                    .replace("\\r", "\x0d")
            );
        }
    }

    // print a trailing newline
    println!("");
}