Learning Rust, Day 1

I decided to start learning Rust and wanted to try something I’ve never done: write about it while learning.

The Idea

• Start out with some basic reading
• Use my favorite card game, cribbage, as a template for working out basic algorithms, data structures, and general syntax

Notes while reading

• Oof, I’m gonna have to get used to static typing again.
• References and borrowing are wacky! It’s intuitive in the “follow the scope” sense but I’m going to have to just work with it more.
• Lifetimes are a clever way to get around “the compiler can’t figure this out” cases, if not clunky syntax-wise.
• I love how common it is to have a “strings are hard” section in any programming language tutorial. By “love” I mean “hate”.
• match makes sense but feels weak compared to Elixir’s pattern matching.
• The Rust book is very good so far. I stopped on the chapter about testing; I’ll have to pick up the rest later.

Working with code

I didn’t get very far today. This is an abbreviated excerpt:

struct Card {
  rank: Rank,
  suit: Suit
}

enum Rank {
  Two,
  Three,
  # etc
  King,
  Ace
}

enum Suit {
  Hearts,
  Spades,
  Diamonds,
  Clubs
}

impl Card {
  fn new(rank: Rank, suit: Suit) -> Card {
    Card {
      rank,
      suit
    }
  }
}

Some notes on this:

• Tests are confusing; they effectively recommend setting up a mod test block in each file for the unit tests. I like the idea of keeping them close to what they test, but I’ve had trouble lining up the various use and mod calls to get it wired up.
• The compiler messages are extremely good.
• The documentation on the difference between a binary and library project are kind of strange? Maybe I’m missing it, I need to just set up both.
• Convention over configuration! Stuff like mod referring to the file name, rustfmt, etc.
• Compile directives are...janky. Stuff like #[derive(Debug)] and #[test] feel bolted on.

That’s all for now!