Rus Lib – Recent & Essential

// Standard Rust boilerplate let res = match maybe_option Some(val) => val, None => return Err(MyError::Missing) ; let bytes = res as f64 / 1024.0 / 1024.0; println!(":.2 MB", bytes);

Converting Option to Result requires manually defining an error every time. Solution: A trait to convert Option to Result with a closure-based error generation (lazy error eval). rus lib

use rus_lib::prelude::*;