Comment by nneonneo

Unclear what you mean by user input - for arguments, `std::env::args()` exists, and for stdin `std::io::stdin()` exists and provides various read functions.

    let mut line = String::new();
    stdin().read_line(&mut line)?;
    println!("input: {}", line);

I suspect that there _have_ been some changes since you last looked - for example, the ? operator lets you propagate errors in a more compact way.