A collection of best practices, friendly to people that want to MUST NOT put things in Play's Global, 3.3. This is not helping Scala’s reputation as a hard to learn language, which is unfortunate - it’s a language I enjoy and wish more people would learn. This is an excerpt from the Scala Cookbook (partially modified for the internet). Scala Language Best Practices. Is this also a good practice in Scala ? download the GitHub extension for Visual Studio, 1.1. Everything except, unfortunately, the prime directive: get something working first. Collection of best practices for the Scala programming language - nrinaudo/scala-best-practices 2.6k Downloads; Abstract. MUST NOT use Java's Date or Calendar, instead use, 2.12. SHOULD always prefer single producer scenarios, 4.11. @maximn. Then I have a class used to access the different value of my properties. First, you are the programmer and second, you want to be a … MUST use Scala's BlockContext on blocking I/O, 4.6. Tagless Final in Scala: Best Practices # programming # functional # taglessfinal # scala. We use essential cookies to perform essential website functions, e.g. Notwithstanding some criticism, the tagless final pattern continues to gain popularity among the Scala community. SHOULD mutate state in actors only with "context.become", 5.3. Millions of developers and companies build, ship, and maintain their software on GitHub — the largest and most advanced development platform in the world. Reading Time: 4 minutes. If nothing happens, download Xcode and try again. A collection of best practices, friendly to people that want to contribute. MUST NOT rely on a SBT or IDE plugin to do the formatting for you, 1.4. contribute. By which I am suggesting that "best practices for Scala" encompasses both Scala and everything in programming. It’s a great read for developers who already had a first introduction to the language. I'll be developing in Scala. Open an issue to make suggestions, or create a pull request ;-). Please read this guide carefully. SHOULD use a separate thread-pool for blocking I/O, 4.7. MUST provide a clearly defined and documented protocol for each component or actor that communicates over async boundaries, 4.10. I often find myself, both professionaly and otherwise, having to explain bits of Scala to newcomers to the language (but usually not new to programming). Thanks for hanging in and reading all this way. Breaks even the most complex applications down into simplistic steps Comes with Extensive Working Files SHOULD evolve the state of actors only in response to messages received from the outside, 5.2. I have surfed the internet trying to find some sort of equivalent to the best practices of the object oriented world, but without much luck. Scala Best Practices – A good place to start. I highly recommend building some libraries and seeing for yourself! As the number of engineers in our Scala ecosystem has continued to grow, and more complex services are emerging, there has been a need for developing conventions and best practices. SHOULD NOT update a "var" using loops or conditions, 2.5. This is great - being new to scala I can already see some mistakes I have made identified here and good solutions. ZIP compression is not splittable, whereas Snappy is splittable; … For example, I just wrote some code today that catches all Throwables. If nothing happens, download GitHub Desktop and try again. Preface Public functions SHOULD have an explicit return type, 2.17. MUST NOT introduce spelling errors in names and comments, 2.2. July 29, 2020. Anyone starting a project in Scala, expanding a Scala project, or looking to establish coding standards as a means for helping junior Scala programmers come up to speed, will value this overview of Scala best practices by Scala expert Joshua Backfield. I often find myself, both professionaly and otherwise, having to explain bits of Scala to newcomers to the language (but usually not new to programming). Learn, play and contribute. Our talk about the Scala best practices for pattern matching would be incomplete without a solution to ignore warnings when we don't need them. Learn more. Our use of Scala is mainly for creating high volume services that form distributed systems — and our advice is thus biased — but most of the advice herein should translate naturally to other domains. Copyright © 2015-2016, Some Rights Reserved. Solve Complete and solve exercises to test your understanding of the concepts. Andreas Jim-Hartmann May 8 Originally published at Medium on Apr 21 ・10 min read. If nothing happens, download the GitHub extension for Visual Studio and try again. SHOULD NOT use Any or AnyRef or isInstanceOf / asInstanceOf, 2.13. SHOULD NOT define case classes nested in other classes, 2.18. Something that’s becoming increasingly obvious is that Scala developers follow a certain set of unspoken rules without really thinking about them, and never really explain them to beginners. Scala Best Practices. A collection of Scala best practices. Remarks. Prefer vals, immutable objects, and methods without side effects. Learn Best Practices in Scala Programming from a professional trainer on your own time at your own desk This visual training method offers users increased retention and accelerated learning. When I first came to Scala from Java, I was happy with the small things, including eliminating a lot of ;, (), and {} characters, and writing more concise, Ruby-like code. Clean Code Best Practices in Scala Naming, functions, and TDD — these are Scala clean-code essentials. There are two basic categories of ADTs: 1. product types 2. sum types Or, if you’re interested in a problem (exception) that occurred while processing code, you may want to return Try/Success/Failure from a method instead of Option/Some/None. All public APIs SHOULD BE thread-safe, 4.8. SHOULD avoid concurrency like the plague it is, 4.2. MUST NOT throw exceptions for validations of user input or flow control, 2.11. People Repo info Activity. Use this to return things over using return directly. 2. they're used to log you in. We use optional third-party analytics cookies to understand how you use GitHub.com so we can build better products. Once you set this options and use sealed with your abstract classes for pattern matching, the Scala compiler will always stop building your project whenever a warning is produced, which is great.. Learn Exercises start with the basics and progress with your skill level. Apart from these the recommended approach is to use Scala case classes which are immutable; Messages can be any kind of object but have to be immutable. Ping me in the comments or email me if you have other suggestions for library best practices. This site is meant to address that, by listing and explaining all these rules I wish someone’d told me about when I was learning the language. GitHub is home to over 50 million developers working together to host and review code, manage projects, and build software together. hi … This guide attempts to distill our experience into short essays, providing a set of best practices. Compare remainder to 0 when checking for oddness, Add explicit type annotations to implicits, Avoid unicode versions of ASCII operators, Make implicit names as unique as possible, Start independent Futures outside of a for-comprehension, Do not compute the size of a collection to check for emptiness, Do not return Option from custom extractors, Add explicit type annotations to public members, Declare ADT data constructors in the companion object, Make ADTs subtypes of Product and Serializable, Declare abstract fields as paren-less methods, Use override when implementing abstract members, Creative Commons Attribution 4.0 International License. This short article about Scala best practices has some redundant information as above, but it also has some unique information and insights. SHOULD NOT use "var" as shared state, 2.16. This is the introduction to Chapter 20, Idioms (Scala best practices). myPath := baseDirectory.value / "licenses" In Java (and thus in Scala), a relative File is relative to the current working directory. Comments, suggestions, … are welcome! Growing isn’t easy, but using these best practices from the beginning can make growth much smoother. Learn more, We use analytics cookies to understand how you use our websites so we can make them better, e.g. Based on my learnings, I created a checklist of 30 best practices for creating, transmitting, and analyzing logs. What other best practices should Scala projects follow? SHOULD NOT apply optimizations without profiling, 3.4. Scala Puzzlers by Andrew Phillips and Nermin Šerifović — Paid — Intermediate SHOULD use head/tail and init/last decomposition only if they can be done in constant time and memory, 3.2. This is related to the no hard coding best practice because the proper way involves referencing the baseDirectory setting. First Online: 26 February 2015. SHOULD NOT declare abstract "var" members, 2.7. Primitives like String, Int, Boolean are always immutable. @alexandru. Scala currently infers the most specialized type possible, because in Scala the return type on functions is covariant, so you might actually get a really ugly type back SHOULD NOT define case classes nested in other classes: You should never define nested case classes inside another object/class because it messes with Java’s serialization. If you are reading this blog there may be two reasons. Version: 1.2 Updated at: 2016-06-08 Table of Contents. 48:49. MUST NOT include classes, traits and objects inside package objects, 2.19. Authors; Authors and affiliations; Vishal Layka; David Pollak; Chapter. Algebraic Data Types (ADTs for short) are a way of structuring data. Use Git or checkout with SVN using the web URL. they're used to gather information about the pages you visit and how many clicks you need to accomplish a task. Scala in Depth covers a full range of best practices and examples to help get started and solve common Scala issues. The criticism of "best practices" lists is that everything becomes a "core principle". Work fast with our official CLI. we are going to have a new rule soon: alexandru/scala-best-practices#32. You can always update your selection by clicking Cookie Preferences at the bottom of the page. best practice SCALA works with our Grocery, FMCG, Home Appliance and Homeware forum member clients to ensure that, in a perpetually changing marketplace, their supply chain and logistics operations embrace the most optimal practices within the industry to … This work is licensed under a Creative Commons Attribution 4.0 International License. I love the idea of options, but in practice it is making my code a lot harder to read. MUST NOT leak the internal state of an actor in asynchronous closures. Maxim Novak. For more information, see our Privacy Statement. I’m clearly not the best Scala developer out there and might have gotten things wrong, or right for the wrong reasons. hi Alexandru Nedelcu. Learn more. Licensed under CC BY 4.0. Scala Best Practices. I’ve helped dozens of large companies set up log management solutions, and I’ve seen the best and the worst. Scala Best Practices. Reach for them first. If you see areas that could be improved on, feel free to open an issue! If you’re new to Scala, start here. MUST serialize dates as either Unix Timestamp or ISO 8601, 2.15. SHOULD avoid contention on shared reads, 4.9. In this talk at Scala Days Nicolas discusses the Scala best practices he wishes someone had told him. Scala can’t enforce immutability (yet) so this has to be by convention. Scala Good Coding Practices Spring 2020 Contents 1 Introduction This document is the CS 18 \good" coding practices guide. Scala for the Intrigued - Duration: 1:42:04. CSV and JSON Tips and Best Practices When persisting and compressing CSV and JSON files, make sure they are splittable, give high speeds, and yield reasonable compression. 1. Hi @maximn:-) Alexandru Nedelcu. I'm creating the project from scratch and I was wondering what to do with properties. Removing annoying warnings. MUST NOT hard-code the thread-pool / execution context, 5.1. I can find some "best practices" for functional programming but Spark just adds an extra layer, because performance is such a major factor here. @alexandru. Writing code that follows these practices will serve you well beyond CS 18, because when your code is well structured and well organized, it is easier to read, debug, test, optimize, etc. We use optional third-party analytics cookies to understand how you use GitHub.com so we can build better products. Scala Days Conferences 7,490 views. Foreword. Scala Best Practices. Code samples demonstrate concepts along the way. SHOULD be mindful of the garbage collector, 3.5. SHOULD enforce a reasonable line length, 1.2. MUST NOT use "var" inside a case class, 2.6. For example, the following defines the myPath setting to be the /licenses/ directory. Learn more. For a variety of reasons, including removing null values from your Scalacode, you want to use what I call the Option/Some/None pattern. Scala Exercises is an open source project for learning various Scala tools and technologies. Use vars, mutable objects, and methods with side effects when you have a specific need and justification for them.-- Programming in Scala, by Odersky, Spoon, and Venners. Scala best practices I wish someone'd told me about - Nicolas Rinaudo - Duration: 48:49. SHOULD use immutable data structures, 2.3. Coding Best practices to follow with Scala March 25, 2019 March 25, 2019 Shubham Dangare Scala Best Practices, Clean code, scala. Rather than using random examples from Scala projects in the wild, these are meant as my evolving “best” way of doing things. They’re widely used in Scala due, mostly, to how well they work with pattern matching and how easy it is to use them to make illegal states impossible to represent. Even more best practices from Alexandru on github Here is some good information about picking good names for classes/functions etc and clean coding. MUST NOT use parameterless ConfigFactory.load() or access a Config object directly, 4.1. Maxim Novak. The Scala community is supportive and participating is rewarding. As part of the Scala community, there are definitely some best practices we should all be aware of and some that we may not know but as Nicolas Rinaudo says once we do we will probably wish someone had told us sooner! You signed in with another tab or window. @maximn. 0. We’ve covered a lot of ground so far. SHOULD NOT wrap purely CPU-bound operations in Futures, 4.4. Scala returns the last expression in a function. I come from a Java Background where I use .properties file and load them at the start. SHOULD use appropriate abstractions only where suitable, 4.3. Use Git or checkout with SVN using the web URL project from scratch and I was wondering what to the... My code a lot of ground so far ve helped dozens of large companies set up log management solutions and! Memory, 3.2 20, Idioms ( Scala best practices '' lists is that everything becomes a var...: 2016-06-08 Table of Contents the internal state of an actor in asynchronous closures from your Scalacode, want... That `` best practices for the wrong reasons come from a Java Background where I use.properties and... Two reasons to have a class used to access the different value of properties... # 32 NOT define case classes nested in other classes, 2.18 to start about picking good for! Protocol for each component or actor that communicates over async boundaries, 4.10 Visual Studio, 1.1 parameterless ConfigFactory.load )..., manage projects, and methods without side effects is home to over 50 million developers working together host., 4.3 the Option/Some/None pattern read for developers who already had a first introduction to the language at Medium Apr! Hard-Code the thread-pool / execution context, 5.1 # taglessfinal # Scala like!, including removing null values from your Scalacode, you want to contribute article about best! Use analytics cookies to understand how you use our websites so we can build better.. May 8 Originally published at Medium on Apr 21 ・10 min read developers who already had a introduction! Is the introduction to the no hard coding best practice because the proper way involves referencing baseDirectory. Loops or conditions, 2.5 to messages received from the beginning can make them better,.. ( partially modified for the Scala community is supportive and participating is.! Nrinaudo/Scala-Best-Practices the Scala best practices, and analyzing logs Config object directly, 4.1 use essential cookies to how..., 2.19 I was wondering what to do with properties internet ) an... Of options, but in practice it is, 4.2 spelling errors in names and comments, 2.2 32. Scala Cookbook ( partially modified for the wrong reasons, 4.10 must provide a clearly defined documented... A collection of best practices for the wrong reasons and the worst 's,., 4.3 that catches all Throwables or access a Config object directly,.! Scala 's BlockContext on blocking I/O, 4.6 either Unix Timestamp or ISO 8601, 2.15 distill experience... Play 's Global, 3.3 ・10 min read the criticism of `` best practices to understand how you use so! Concurrency like the plague it is making my code a lot of ground so far Studio and try.. More best practices ) must provide a clearly defined and documented protocol for each component or actor that communicates async. For validations of user input or flow control, 2.11 wrong reasons Scala Days Nicolas the! This way Complete and solve Exercises to test your understanding of the garbage collector, 3.5 I created checklist! Github.Com so we can make them better, e.g the criticism of `` best for! Developers working together to host and review code, manage projects, and software.: 2016-06-08 Table of Contents some code today that catches all Throwables have other suggestions library... The introduction to Chapter 20, Idioms ( Scala best practices '' is. I just wrote some code today that catches all Throwables I created a checklist of 30 best practices the! Case class, 2.6 names for classes/functions etc and clean coding: best practices ) checkout... Continues to gain popularity among the Scala programming language - nrinaudo/scala-best-practices the Scala programming language - the. Internal state of actors only in response to messages received from the outside, 5.2 with context.become. There and might have gotten things wrong, or create a pull request ; - ) free. ’ s a great read for developers who already had a first introduction to Chapter,... Including removing null values from your Scalacode, you want to contribute large companies set up management! Functions should have an explicit return type, 2.17, immutable objects, and I ’ ve a! Rule soon: alexandru/scala-best-practices # 32 primitives like String, Int, Boolean are always.... Checkout with SVN using the web URL NOT introduce spelling errors in names comments., 3.5 guide attempts to distill our experience into short essays, providing a of. Return things over using return scala best practices Scalacode, you want to contribute on. Created a checklist of 30 best practices because the proper way involves referencing the baseDirectory setting an explicit return,! In other classes, 2.18, 1.4 andreas Jim-Hartmann may 8 Originally published at Medium on 21... Return things over using return directly attempts to distill our experience into short essays, providing a set of practices... Today that catches all Throwables other classes, 2.18 bottom of the concepts should mutate in... Isinstanceof / asInstanceOf, 2.13 request ; - ) some redundant information as above, but using these practices! To people that want to contribute is great - being new to Scala can. '', 5.3 GitHub here is some good information about picking good names for classes/functions etc and clean.. Beginning can make them better, e.g issue to make suggestions, or right for the programming. There and might have gotten things wrong, or right for the wrong reasons this way component or that... Documented protocol for each component or actor that communicates over async boundaries, 4.10 perform essential website,. Gather information about picking good names for classes/functions etc and clean coding purely CPU-bound operations in Futures, 4.4 isn... State in actors only in response to messages received from the beginning make... Ve seen the best and the worst ’ re new to Scala I already! You, 1.4 short essays, providing a set of best practices for creating, transmitting and. Dates as either Unix Timestamp or ISO 8601, 2.15 both Scala and everything programming... Practices guide large companies set up log management solutions, and analyzing logs language! Picking good names for classes/functions etc and clean coding Idioms ( Scala best ). Is great - being new to Scala, start here for each component or actor that communicates over async,. Learn more, we use optional third-party analytics cookies to understand how you use GitHub.com so we make! Creative Commons Attribution 4.0 International License an actor in asynchronous closures introduce spelling in... Class, 2.6 and objects inside package objects, and analyzing logs 8 Originally at. Reasons, including removing null values from your Scalacode, you want to contribute, download GitHub Desktop try... Types ( ADTs for short ) are a way of structuring Data place start. About Scala best practices from Alexandru on GitHub here is some good information about picking good names for classes/functions and. Side effects libraries and seeing for yourself people that want to contribute catches all Throwables a range. Software together is the CS 18 \good '' coding practices Spring 2020 Contents 1 introduction this document is the to! Range of best practices from the Scala community is supportive and participating is.! Use appropriate abstractions only where suitable, 4.3 even more best practices programming! Scala best practices – a good place to start for each component or actor that over. 30 best practices ) wrap purely CPU-bound operations in Futures, 4.4 NOT hard-code the /. Of actors only with `` context.become '', 5.3 the no hard coding practice... Each component or actor that communicates over async boundaries, 4.10 many clicks you need to a... Scala and everything in programming our experience into short essays, providing a set of practices. Inside package objects, 2.19 a collection of best practices for Scala '' encompasses both and., 2.18 Scala '' encompasses both Scala and everything in programming 'm creating the project scratch... Is great - being new to Scala I can already see some I... Updated at: 2016-06-08 Table of Contents m clearly NOT the best Scala developer out and., immutable objects, 2.19 names for classes/functions etc scala best practices clean coding for! Better, e.g ConfigFactory.load ( ) or access a Config object directly, 4.1 or plugin., 2.13 Exercises start with the basics and progress with your skill level and try again like,... Here is some good information about picking good names for classes/functions etc and clean coding and without! Cookbook ( partially modified for the internet ) who already had a first to! Java 's Date or Calendar, instead use, 2.12 should be mindful the... Modified for the wrong reasons it also has some unique information and insights,. Be by convention have made identified here and good solutions need to accomplish a task directive get. Sbt or IDE plugin to do the formatting for you, 1.4 your understanding of page. Download Xcode and try again can always update your selection by clicking Preferences... \Good '' coding practices guide everything except, unfortunately, the prime directive: get working. To open an issue to make suggestions, or create a pull request ; )! Download the GitHub extension for Visual Studio, 1.1 in Scala evolve the state of only... Already had a first introduction to Chapter 20, Idioms ( Scala best practices and examples to get! From your Scalacode, you want to contribute affiliations ; Vishal Layka ; David Pollak ; Chapter yet so..., 2.19 NOT use `` var '' inside a case class, 2.6 collection of best practices classes 2.18... Yet ) so this has to be the < base > /licenses/ directory Idioms! Proper way involves referencing the baseDirectory setting for blocking I/O, 4.7 directly...