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  • Default User Avatar

    I missed to speak about Person::greet. No more sentences, just code:

    fn greet(&self) -> String {
        let start = "Hello, my name is ";
        if self.last_name.len() > 0 {
            format!("{}{} {}", start, self.first_name, self.last_name)
        } else {
            format!("{}{}", start, self.first_name)
        }
    }
    

    Full code: https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=6f5a936cd0482aceb70bb839fceb433c

    EDIT: I would have optimized by implementing std::fmt::Display.

  • Default User Avatar

    This is a macro, not a function, so you just remade my code as a function.

    I just applied most of my suggestions to made them more clear. I also missed detail about using standard traits. It offers you a lot of advantage thank to generic implementation, you benefit from other traits that have generic implemention over implemented traits.

    For example by implementing std::default:Default, you are able to create default std::option::Option.

    Such std::convert::TryFrom would be better than std::str::FromStr !

    Tell me how to fix the macro if you need to correct me.

    If this is just a "macro-to-function" transformation, you will surely be able to do.

    Next time when displaying code in markdown do this:

    Sorry, long time I haven't post on Codewars. I was just hoping auto-detection due to context and content (just as most services do)

    Now tell me why you used &str

    &str are slices (looks like a "partial" burrow over piece of data). They avoid memory duplication & ownership. It also lets you abstract over &'static str and String burrows.

    Now tell me when you used if

    As it was specified: two-way alternatives. To be honest, you should be able to directly pattern match over the array names.


    Here we go:

    macro_rules! createPerson {
        ($name: expr) => {
            {
                let names = $name
                    .split(' ')
                    .collect::<Vec<&str>>();
                
                let (first_name, last_name) = match &names[..] {
                    &[first]       => (first, ""),
                    &[first, last] => (first, last),
                    _              => panic!("Entered wrong amount of words"),
                };
                Person::new(first_name.to_string(), last_name.to_string())
            }
        };
        ($fname: expr, $lname: expr) => {
            Person::new($fname, $lname)
        }
    }
    
  • Default User Avatar
    1. In createPerson avoid creating a "default" instance that NEVER be used.
    2. May be add a slice-based (&str) constructor
    3. if are expressions, use it :)
    4. if may alternate on constructor parameters that each calling constructor
    5. std::str::FromStr sounds better
    impl FromStr for Person {
        type Err = String;
        
        fn from_str(s: &str) -> Result<Self, Self::Err> {
            let names = s
                    .split(' ')
                    .collect::<Vec<&str>>();
            
            let (first_name, last_name) = match names.len() {
                1 => (names[0], ""),
                2 => (names[0], names[1]),
                _ => Err("Invalid word count".to_string())?
            };
            Ok(Self::new(first_name.to_string(), last_name.to_string()))
        }
    }
    
  • Default User Avatar

    get() always throws an ExecutionException which wraps exception thrown by task.

    In order to log exception, it is better to handle them in afterExecute instead of wrapping task.

    To check exception, I suggest you take a look at JUnit Rule ExpectedException (https://github.com/junit-team/junit4/wiki/Exception-testing#expectedexception-rule) or at AssertJ exception assertion (http://joel-costigliola.github.io/assertj/assertj-core-features-highlight.html#exception-assertion)

  • Default User Avatar

    Why compute breaks, if you can simply check n & m ?

  • Default User Avatar

    It seems you're not trying to compile but to execute. Message explain that is looking for a "main" methods (https://docs.oracle.com/javase/tutorial/getStarted/application/index.html#MAIN)

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