I teach a course in Programming Paradigms. Last year I used Elm as an example of (Functional) Reactive Programming. This summer I noticed that Elm is no longer FRP (according to http://elm-lang.org/blog/farewell-to-frp). I'm looking for another vehicle, one for which I don't have to first teach a lot of syntax.
Reactive Programming in JavaScript seems way too complex. My students will have learned some Scala, but I haven't found a good tutorial on RP in Scala.
Suggestions, anyone? Requirements: reactive, simple syntax.
You can also check Reactor for Spring ecosystem https://github.com/reactor/reactor-core/blob/master/README.md
I suggest RxJava with Java8. It is well documented and maintained. There is a lot of materials- books, articles, tutorials, conference talks, etc.
'reactive, simple syntax'..
I do not see much in common between syntax and being reactive. Java8 has excellent free IDE support (Intellij or Eclipse). For me, it is important in learning new language than paradigim- more important than language itself.
Related
Despite having read "Programming in Scala" several times, I still often finds important Scala constructs that were not explained in the book, like
#uncheckedVariance
#specialized
and other strange constructs like
new { ... } // No class name!
and so on.
I find this rather frustrating, considering that the book was written by the Scala "inventor" himself, and others.
I tried to read the language specification, but it's made for academics, rather than practicing programmers. It made my head spin.
Is there a website for "Everything "Programming in Scala" Didn't Tell You" ?
There was the daily-scala Blog, but it died over a year ago.
Currently, we're working on a central documentation site for scala-lang.org. We're hoping that this solves a lot of the documentation issues that new users face. More details on this effort can be found at http://heather.miller.am/blog/2011/07/improving-scala-documentation/, but in summary...
Believe it or not, there are a lot of documents that the Scala team has produced but which simply aren't in HTML or are otherwise difficult to find. Such as Martin's new Collections API, his document on Arrays, or Adriaan's on Type Constructor Inference.
One goal of such a site is to collect all of this documentation in one place, in a searchable, organized, and easy-to-navigate format.
Another goal is to collect excellent community documentation out there, and to put it in the same place as well. For that, we are actively looking for quality (article/overview-like) material with maintainers. Examples include the Scala Style Guide, and Daniel Spiewak's Scala for Java Refugees.
Yet another goal is to make it easy for contributors to participate- so the site is built from RST source, which will live in a documentation-only github repo at https://github.com/scala/scala-docs.
So, in short, something better is on it's way, and contributors are very welcome to participate.
EDIT: http://docs.scala-lang.org is now live.
Several documents considered to be rather detailed or even obscure are already available. This includes all "Scala Improvement Proposals" (the proposals produced when new language features are suggested, and which are usually very detailed, and written by the implementers themselves). Also available is the entire glossary from Programming in Scala, Scala cheatsheets, amongst many other documents. The bottom-line of the site is to be community-focused and contribution-friendly-- so, free, and totally open. Suggested topics to cover are also welcome.
Take a look at scalaz and typelevel librairies (shapeless, spire, etc.), they rely on many advanced features of Scala.
*scalaz was for a time part of typelevel, but it is no more the case.
Josh Sureth's book goes a little beyond the usual. It's not as far as I'd like but I'm not his core audience - still, there's a lot of good stuff in there.
http://www.manning.com/suereth
Scala IRC: irc://irc.freenode.net/scala
Scala forum: http://scala-forum.org/
Blogs: Just look at http://planetscala.com/
Programming Scala (Wampler, Payne): http://ofps.oreilly.com/titles/9780596155957/
Programming in Scala (Odersky, Venners, Spoon) - good but Scala 2.8: http://www.artima.com/pins1ed/
The new documentation page is online:
http://docs.scala-lang.org/
I've kept a library of advanced Scala resources, primarily talks and blog posts. It's updated pretty regularly as I find new, interesting content.
Happy to add new links to it if anyone has recommendations.
Try to read SBT Source: https://github.com/harrah/xsbt/wiki
Its a good exercise. Also check out the book 'scala in depth' : http://www.manning.com/suereth/ by
Joshua D. Suereth
I believe there are a lot of good answer here. But as a sharing of experience. I have been coding Scala for 2 year (not my full time job), and been progressively better at it. My project is 97% Scala, and I have been able to do most of it with:
Programming Scala
The scala-user list
Stackoverflow
This cover most of the need for the "user" side of Scala, meaning all you need to create working application. However if you want to write some more complex code, or create powerful typed libraries you definitely need more.
If you want to go beyond the basics and are prepared to delve deeply into type system, and libraries, then the alternatives I use:
Use the community, scala enthusiast are really nice. I have worked with folks form Specs, Scalaz and Lift.
IRC is really good and some of the core contributors to some of the big library frequently show up.
Jump to source code, but don't try to understand everything. Scala type system can be daunting, however you normally don't need to understand 100% of it to use it.
If you really need to get into the nitty gritty details, hit the language specs, development list, and get to know the key people.
However you can really be very effective in Scala without needing to understand every single bit of the language.
What are some good online articles or videos you've seen that would be most likely to get a developer interested in Scala? I'm looking for an introduction that is brief & to the point that dives right into example code, and would leave a developer who does not know Scala wanting to learn more about it.
Try in this order:
Pragmatic Real-World Scala - This video shows off all kinds of things that would make a Java developer drool.
Programming In Scala - This is simply a great general-purpose programming book. In addition to being a gentle, clear introduction to the language, it's also a fantastic introduction to functional programming concepts and language design. Even if you hate Scala,
this book will make you a better programmer.
Scala For Java Refugees - Very well-written mostly gentle introduction to major Scala concepts.
Another tour of Scala - A Java-centric breakdown of fundamental Scala features.
i went to this talk, it was excellent. can't tell if it is still there due to our internet restrictions, if it's not i'll delete this post.
http://powerhost.powerstream.net/008/00102/100203Scala.wmv
I'd go straight to the horse's mouth, the Scala website itself: Code Examples.
http://www.escalatesoft.com/screencasts
Escalate software is in the process of creating a series of screencasts for Scala information sharing and training purposes. The first available screencasts are provided here for free and cover the new features of Scala 2.8. In the longer term we will create training materials in the form of these videos along with supporting material that will be for sale from this and other sources as well.
http://blog.jaoo.dk/2009/03/09/an-introduction-to-the-scala-programming-language-by-bill-venners/
Take a look at the following presentation by Jonas Bonér (a well known figure in the Scala community, responsible for the AKKA actors concurrency framework). I'm sure this will whet the appetite for Scala.
http://www.infoq.com/presentations/Scala-Jonas-Boner
german introduction, maybe useful for you: http://www.rheinjug.de/videos/gse.lectures.app/Player.html#Scala
I would recommend Chapter 1. Zero to Sixty: Introducing Scala of the Programming Scala book by Dean Wampler and Alex Payne. The rest of the book is also great. The book is freely available online.
EDIT
I recently bought and read the Atomic Scala book by Bruce Eckel and Dianne Marsh. This is the best book I have read so far for anyone wanting to learn Scala.
Is there a source, which I could use to learn some of the most used and popular practices regarding Actor-/Agent-oriented programming? My primary concern is about parallelism and distribution limited to the mentioned scheme - Actors, message passing.
Should I begin with Erlang documentation or maybe there is any kind of book that describes the most important building blocks when programming Actor-oriented?
(Most useful examples would be in Scala or F#)
The Erlang and Scala's Akka are most popular and have large community. In case you want to know ML-based style there is JoCaml. They have simple intro text and collection of more formal papers. I'm using JoCaml about two years in my research work and very happy with it. Also, you can find many examples of the F# mailboxes usage to implement actor-style message passing.
For a colorful and interesting explanation I'd recommend to read some entries on this blog
Other than that, we welcome you to the Akka mailinglist!
With regards to the usage of Actors in Scala, you might want to look into the Akka framework. It has good documentation, and here they have a list of articles and presentations with many examples.
You won't find much in the Erlang documentation that explicitly talks about Actors. The documentation and recent Erlang books explain how to use concurrency/distribution/message passing in the Erlang context. As an aside we hadn't actually heard of Actors when we developed Erlang.
we are considering Scala for a new Project within our company. We have some Junior Programmers with only PHP knowledge, and we are in doubt that they can handle Scala. What are your opinions? Some say: "Scala is a complicated beast!", some say: "It's easy once you got it." Maybe someone has real-world experience?
"My coworkers will not understand Scala" is simultaneously overstating its difficulty and insulting your coworkers.
Scala is not that difficult. It's just another programming language. Any trouble that junior programmers have with Scala is going to be more or less the same trouble they would have with any other language.
Your coworkers are smart. Of course, I don't know them, but it's a pretty safe bet unless your company is the kind of organisation that hires stupid people, in which case, you have bigger problems.
That said, at my company we have some core products developed in Scala, and we don't find that people have any more trouble with it than Java. The code is generally more clear and concise, easier to generalise and reuse, etc.
I guess Scala could be used as a "beginners" language. Even though there are tricky ideas behind it, you dont have to use/explain them in the beginning. If you explain pure OO with Scala, I would say it is straight forward and easily understandable. As Scala reduces a lot of code overhead from other languages it might even be easier to learn concepts with Scala than with Java/C++.
A major drawback I see with Scala as a beginner language is the lack of documentation. Don't get this wrong, the official Scala doc is very good and also the few books that are available are quite useful to get the details of the language, but those have not been written for beginners. For example in Java you find hundreds of books titled something like "Learning OO with Java" you wont find that for Scala which may be a show stopper.
As Hannes mentioned, only do new language introductions within research projects and not productive or even flagship projects. If you have some juniors, that makes the situation even better, take some internal tool, you always wanted and needed and let them create it during a research project. This is also a nice opportunity to experiment with different development-processes. And your juniors most probably like to be challenged and will deliver a good prototype and a very well proofed opinion if Scala can be used as a beginner language.
I believe that most people moving to Scala are experienced and enthusiastic coders. I'd suggest that you get in-house experience with a Scala project with your senior programmers first before forming a strategy for mentoring your junior coders. I'd also suggest that you only involve people who are eager to join in.
I would advocate it. But with the proviso that you have clear guidelines on what language features are acceptable for your team. For example, coding primarily in an imperative style (which is familiar for Java-trained people), or perhaps limiting the employment of recursion or closures.
Also plan for seniors to mentor the juniors. This may take the form of any combination of: pair programming, code reviews, info sessions, regular discussion forums, etc.
The opportunity that scala presents for vastly improved coding on the JVM is too great to pass up. When your seniors get into it I would not be surprised if they find renewed passion for development. When your juniors get into it they will be learning best practice JVM development from the start.
If you choose to go this route, perhaps they'll find easier to use the Scalate framework than a more traditional one like Lift, since it allows mixing HTML with Scala, much in the same way as PHP works.
Scala is a very 'normal' programming language. Any programmer should be able to learn this language. The people that have difficulties learning Scala mostly are experienced with imperative languages and are surprised by the functional concepts. So unexperienced programmers may learn it even faster. In my opinion should be no problem, to assign it to juniors. From a management point of view, I would assign a junior and a senior developer as a team (or more of both, depending on the size of the project).
I think it depends whats more importent for you. If you want to learn as possible about OO Programming and the standard stuff its a bad idea.
But what you really give them is a opportunity to learn something really cool and unique. Witch can be good motivation. Scala has many cool stuff in it. If you can handle Scala you can handle a lot of otherstuff as well.
Talk to the Programmers (all of them) and tell them why you wanne to use scala. Ask if the have to motivation to make and learn something not everybody can do and go the extra mile?
If the are go with it!
My initial thought would be that Scala will be too heavy for them but then I guess because Scala is an OO/Imperitave/Functional hybrid, one could introduce them to the OO/Imperative part of scala until their comfortable, but then again they will probably have bad PHP habits in Scala since scala authors mostly prefer the functional style over the imperative one.
So, it could work, but I would do it for a research project, and definately not for a flagship one.
Edit: Perhaps this should be said also: It seems that functional/OO hybrids like Scala is becoming more popular especially because of how functional languages handles parallel processing as opposed to how we know it in languages like in Java. The amount of cores found in a chip is increasing rapidly, so this is important. However, mentioning PHP, it seems that you are developing web server scripts where threading is less important. PHP doesn't even have threads.
This raises another point. Do you want to develop Scala Web applications i.e. Lift. If so then you have a doubled up learning curve which should also be considered.
Imagine that you would have picked Java and asked whether they could handle Java. If your answer is they could, then they can probably handle Scala.
Scala is only marginally more difficult due to:
No great IDE support. The support ranges from poor to good. Not necessarily an issue for a PHP programmer.
Documentation not as rich as Java
Both Java and Scala have new challenges for a PHP programmer (JVM, new libraries, compiled language, statically typed).
I don't think Scala is a complicated beast, but you do need to understand some of the syntactic sugar and design principles, which would be true of learning Java as well.
Yes, if...
Strategic decision has been made to go with Scala
Company can handle the hit (financial and time) that will come from the steep learning curve.
No, if...
No senior Java, C# or C++ programmers can be put on the project too
Can't find a Scala programmer to act as a lead
Programmers don't have the patience to learn Scala or deal with a language where Jars (libraries) are scattered all over the place, rather than in one or two neat packages like PHP.
*Note: if the junior programmers were C++, C#, or Java Software Engineers rather than PHP, then my answer would be different like, Go for it!
I would not recommend it. My experience of Scala is only from homebrew projects, but I would imagine the currently lousy IDE support, quite frequent API changes and a very flexible syntax (that allows one to hang himself and everybody else participating in the project) would cause a lot of problems in a bigger, more official project.
Give them IntelliJ and throw 'em in the deep end.
Here is a blog post I recently stumbled upon:
http://james-iry.blogspot.com/2008/07/java-is-too-academic.html
It shows that even Java can be too academic to be understood by programmers which have no experience in functional programming. On the other hand, Scala allows to write code the "imperative way", so you can avoid all the FP stuff if you do not understand it. In my opinion, Scala is much more concise than Java, so I guess a "junior programmer" should be able to handle it.
As a academic project of 6 months in college me and my 3 friends are going to implement "Distributed Caching" in scala language.
Being new to both of these concepts and this being our first project I would be really happy if you guys could provide some direction.
I am currently learning scala.
Please let me know which particular features of language to be learned for this particular project.
Any online resources for learning distributed caching.
thanks in advance
You could have a look at Terracotta and especially at its uses in implementing Distributed Caching. You could have a look at the source code of the open source edition of Terracotta. Also, you could even consider Terracotta as your framework for building the distributed cache. I don't have any personal experience in using Terracotta with Scala, but it has been done.
Features of the language... Try starting with the Programming in Scala book. It's a very good resource. If you want to do any concurrency you will have to be proficient in using Actors. I would recommend having a look over all the features of Scala. Each one has its uses and you will need to know at least a bit of them to recognise situations in which to use their power. :)
-- Flaviu Cipcigan
You might want to look at the project Velocity page.
In MSDN also there is an article about distributed caching in general.
I'm not sure, but I think the Akka project might is already doing what you're looking for (and a whole lot more). Perhaps you can take inspiration from that.