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Let me introduce you to Luis Lavena. Hello everybody. The tough part about being after lunch is that everyone will want to take a nap. So, let's talk a bit about Ruby and Crystal, the Crystal programming language.
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Don't worry; it was just me misplacing my screen. So, my name is Luis Lavena. You can find me on Twitter; feel free to say whatever you want. On GitHub, you can find my username as well, where I upload all sorts of things.
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To give you a bit of background, I am the creator of Ruby Installer for Windows. So, if anyone has suffered at some point working with Ruby on Windows, that's my fault. Now that I'm somewhat retired after ten years, I think I did some good; the community has grown so much, and nowadays, Ruby runs really well.
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I'm also a Ruby co-committer. While I'm not as prolific as Nobu or others, some of the comments associated with Ruby for Windows are connected with the work we did on Ruby Installer. I work for a company called Is 17, a digital product agency that sponsored my trip here.
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I actually moved to France as an expatriate Argentinian, and I want to thank them for hosting me here. Now, this is a technical talk, so before we jump into deep technical stuff, I want to give a warning: I'm from Argentina, and tomorrow there's a French match. Now that I'm here as an expat, it makes things complicated.
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So, let's talk more seriously about Crystal and Ruby. What differentiates them? We're going to focus on the aspects of compiled languages and how they generate machine code, and what that means compared to interpreted languages.
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Ruby works by starting with the 'require' command, reading the source code, and converting that into tokens that represent your code. It then parses this and builds what's called an Abstract Syntax Tree (AST). From there, it creates an instruction sequence, which tells the Ruby virtual machine how the code works.
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This instruction sequence runs inside the virtual machine, now known as YARV (Yet Another Ruby Virtual Machine), from Ruby version 1.9 onwards.
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Now, how does that compare to a compiled language? A compiled language also reads the source code, tokenizes it, and parses it through a lexer. However, instead of building an instruction sequence, it generates native code that will run natively on the operating system.
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This means that it compiles the native code, links all those objects, and generates a final executable. Depending on the compiler's complexity, there might be an additional phase between parsing and generating code that analyzes your code, performs type checking, and executes optimizations.
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At this point, the most interesting part happens during the analysis phase, which I like to call 'magic.' Let's take a look at a specific example: the Crystal language.
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Crystal has similar phases to a compiled language but also introduces some unique features. Its syntax is inspired by Ruby, and it can directly bind to C libraries without the need for a custom extension API. This means you can write directly in Crystal without any extra layers.
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While it lacks some dynamic typing and metaprogramming techniques found in Ruby, it offers macros. Macros are automatic code expansions that can be even more powerful than metaprogramming techniques because they allow you to analyze what you generate at compile time, knowing in advance if it will work or not.
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The syntax is similar to Ruby, and it generates a single-file native executable on your machine. Crystal's compiler is built on LLVM, which offers powerful optimization capabilities.
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Now, let's focus on one specific aspect: type inference. Type inference in programming means that you have various data types—like integers, floats, and strings—that represent data or objects in your program. Inferred typing means these types do not need to be declared explicitly.
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If you're familiar with C language, when you do not define a type, the C compiler will complain. However, in an inferred language like Crystal, it deduces the type based on context as it parses the code.
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For example, if you have an array of integers, Crystal will analyze the values and deduce the type. You can define variable 'A' as an array of 32-bit integers and another variable 'B' as an array containing a number, a string, and a character. If you try to add an incompatible type, Crystal will complain during compilation, ensuring types are checked before run-time.
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This checking happens at compile time, leading to better code, as you're alerted to potential problems before you run your tests. The same applies to method calls. For instance, if you define a method that adds two values together, and you accidentally attempt to add a string and a character, Crystal will throw an error at compile time.
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Additionally, if you try to call a method on an undefined variable or nil value, Crystal will let you know during compilation, which is a significant improvement over Ruby’s run-time errors. You can implement techniques in Crystal that can help you handle nil values effectively.
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As an example, if you work with a worker object, you might have code that checks if the worker variable is defined before performing operations on it. This method of manipulating potential nil values will help when transitioning back to Ruby, making it easier to recognize possible errors.
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Another challenge we encounter involves accessing variables across threads. Ruby is a single-threaded language, but it can still face issues with global variables being modified by another thread. To mitigate this, you might capture variable values into local variables to ensure consistency and reliability.
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By doing so, you guarantee that the value accessed is the expected value at that moment, thus avoiding potential runtime errors.
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We discussed techniques you can borrow from compiled languages. Now let’s talk about optimization techniques. One of these is related to load time. When working with Rails applications, we know that load times can be significant.
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When you're deploying your application, you need to manage load time carefully to ensure better performance. This involves using techniques like rolling deployments to maintain uptime while you're deploying updates.
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The time it takes to read files, tokenize them, build instruction sequences, and execute them impacts your overall application performance. For every require call in your Ruby project, this process repeats, further adding to your application’s loading time.
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This is where the introduction of techniques like Bootsnap comes in. Bootsnap is a gem designed to optimize load times by tracking files that need to be loaded and keeping a cache of compiled bytecode.
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This allows your application to avoid re-compiling files that have already been processed, leading to a significant reduction in boot time.
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In fact, integrating Bootsnap can provide up to a 30% performance improvement in your application’s boot time, depending on application size and complexity.
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Switching gears, let's discuss installation times and dependencies. As many find, updating dependencies like Nokogiri can be time-consuming due to the need to compile native extensions.
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Using a tool like 'Gem Compiler' allows you to precompile gems for your platform, drastically reducing installation time and managing bandwidth. This means you can optimize both the time and resources needed for dependency installation.
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In short, by using precompiled binaries, you gain efficiency. Given the time spent compiling extensions each time you deploy, having a precompiled version will save resources and speed up your deployment process.
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Now let's wrap up with optimization techniques involving code style. Consistency in code formatting is essential. This applies particularly to newcomers who may wish to contribute to projects.
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By enforcing a standardized style guide, you streamline communication and minimize disputes about coding styles, allowing teams to concentrate on functionality rather than style.
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There are tools available to aid in code formatting, similar to Go and Rust, which help maintain a consistent codebase while allowing developers to focus on feature development.
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For Ruby, 'RuboCop' is a formatter that applies the Ruby style guide recommendations and can be integrated into your CI environment. This means that every time someone creates a pull request, you can ensure their code adheres to your style guidelines.
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With these techniques combined, we can create better, cleaner Ruby code by adopting philosophies and strategies from compiled languages.
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As we apply these strategies, we improve our workflow and ensure our open-source projects create a welcoming environment for newcomers. So, let’s embrace these improvements for a more efficient and streamlined Ruby development experience.
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Links to improve your load time, use Bootsnap from Shopify, incorporate pre-compiler gems, and apply code formatting techniques with RuboCop are available for reference.
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Thank you very much for your attention.
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Thank you, Luis. Okay, one question. You can find me outside if you need to discuss anything.
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Thank you for the talk! I have a question about optimization. I've learned a lot from interpreting languages and compiling them. What if I want to optimize my deployment by compiling my gems before installing them?
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That's a very good question. The drawback is that if you compile on your local machine, it may not work on your server due to differences in the operating systems. Instead, you could pre-compile for the appropriate platform.
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You can also enhance your development workflow by pre-compiling gems that everyone on your team uses, streamlining the process while saving time.
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Thank you again.