use std::collections::HashMap;
fn main() {
   let mut operations: HashMap<String, String> = HashMap::new();
        operations.insert("dup".to_string(),"dup".to_string());
        operations.insert("drop".to_string(),"drop".to_string());
        operations.insert("swap".to_string(),"swap".to_string());
        operations.insert("over".to_string(),"over".to_string());

   match operations.get("dup").cloned() {
        Some(f) => {
            match f {
                "dup".to_string() => println!("{}", f),
                _ => println!("{}", "else")
            }
        }
        None => println!("{}", "test_none")
    }
}