Tagged Questions

Scala is a general purpose programming language principally targeting the Java Virtual Machine. Designed to express common programming patterns in a concise, elegant, and type-safe way, it fuses both imperative and functional programming styles.

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2
votes
4answers
269 views

How to promote Scala to the management?

As a developer I like Scala and could tell the management about technical benefits of the language. But even if management understands that a superior technology has business impact, I fear that they ...
4
votes
4answers
416 views

Big switching from one platform to another [closed]

As an example I want to switch from C#/.NET to Scala/Jvm. I'm working as a self-employed and I'm free to choose my favorite language/platform. Having more than 8 years of experience in C#/.NET leads ...
7
votes
1answer
816 views

Why is the Scala Option type not called Maybe, just as in Haskell?

Why is the Scala Option type not called Maybe, just as in Haskell? Maybe makes a lot more "semantic sense" to me, but maybe Option has different behaviour I am not aware of. Is there any particular ...
16
votes
4answers
4k views

What is the difference between a Future and a Promise?

What is the difference between a Future and a promise? (In Akka and Gpars.) They look the same to me as both block and return the value of the future when get is called and a promise is to get the ...
2
votes
2answers
940 views

Should I use semicolons to delimit Scala statements?

I'm used to delimit statements by a semicolon from Java, so naturally I do it in Scala code too. I also feel that the code is easier to read, because it's evident where one statement ends and another ...
2
votes
1answer
651 views

Is it worthwile to learn/use Play framework (for Scala or Java) if I don't use the MVC in it

I prefer Single Page Application to server side generated HTML. I am sensible to the pitch of "high productivity" delivered by Play. Now if I don't use the HTML generation part, is it still ...
0
votes
2answers
854 views

How do I initialize a Scala map with more than 4 initial elements in Java?

For 4 or fewer elements, something like this works (or at least compiles): import scala.collection.immutable.Map; Map<String,String> HAI_MAP = new Map4<>("Hello", "World", ...
0
votes
1answer
165 views

Scala string interpolator: ad-hoc feature of general construct?

In Scala 2.10 a new string interpolator feature has been added (see here). For example val name = "James" println(s"Hello, $name") // Hello, James What is not clear to me is whether this feature ...
10
votes
2answers
1k views

How is Nothing a subtype of every other type in Scala

I am taking Martin Odersky's coursera course on functional programming with scala, and for now I have learned two things that together don't make sense: Scala doesn't support multiple inheritance ...
6
votes
5answers
3k views

Is Clojure's syntax really simpler than Scala's? [closed]

Argument which is always made in favour of Clojure is that. The syntax is simpler and there is only one way of expressing code with no complicated rules. However Scala has loads of different types ...
7
votes
4answers
904 views

Why does Scala use the '_' operator for package import instead of '*' as in Java?

In my opinion, one of the greatest things about Scala is its interoperability with Java and its similar syntax. One thing that I found strange is the use of the _ operator for package wilcard imports ...
5
votes
2answers
1k views

Node.JS or Scala for mobile and web apps [closed]

I am coming from a php background with some python as well. I want to start working on a different language for both web and mobile development. I am also interested in real time apps dealing with ...
2
votes
4answers
1k views

What are the practical benefits of LISP like syntax which Clojure uses over Java like syntax of Scala?

I spent couple of months learning Scala and got overwhelmed by number of different constructs it had, After looking at partial functions, partially-applied functions, pattern matching, actor syntax, I ...
4
votes
2answers
268 views

How are Scala Traits implemented in the JVM?

I have been reading about traits in Scala. They are pretty amazing. I am curious how they extend a class without actually resulting in multiple inheritance. I know that the JVM doesn't support ...
34
votes
8answers
3k views

Is memory management in programming becoming an irrelevant concern?

Background I revisited an old (but great) site I had not been to for ages - the Alioth Language Shootout (http://benchmarksgame.alioth.debian.org/). I started out programming in C/C++ several years ...
2
votes
1answer
1k views

Using akka actors with service spring beans

Do you think that using akka actors in front of transactional service beans, is a good idea ? Actors are waked up by a facade used by a client application, and actor use a message to handle right ...
3
votes
1answer
588 views

Can Objective C categories serve the same purpose as Traits do in Scala?

The statement of the question seems little abstract to me, so please read the details below. Since the time when C++ was the first choice Object Oriented Language for almost anything, we had a big ...
0
votes
1answer
1k views

Method overload in scala

I know method overload is not allowed in Scala and I have read some posts regarding the reasons. But still, I see some functions overloaded in Scala library (example: println). I want to know how it ...
25
votes
2answers
2k views

Applying Denotational Semantics to design of Programs

I've read a bit on denotational semantics (DS) and I'm very intrigued about the process of designing computer programs where types and functions have strong and clear mappings to mathematics. Are ...
11
votes
2answers
1k views

How will the new development of Java influence its interoperability with languages like Scala and Clojure?

As far as I understand, both Scala and Clojure have been designed as new languages that depend on the JVM, and easily integrate with Java code, in the sense that they allow to use Java classes ...
22
votes
6answers
2k views

Functional programming compared to OOP with classes

I have been interested in some of the concepts of functional programming lately. I have used OOP for some time now. I can see how I would build a fairly complex app in OOP. Each object would know how ...
7
votes
1answer
1k views

What's the problem with Scala's XML literals?

In this post, Martin (the language's head honcho) writes: [XML literals] Seemed a great idea at the time, now it sticks out like a sore thumb. I believe with the new string interpolation ...
9
votes
3answers
4k views

Fastest Functional Language

I've recently been delving into functional programming especially Haskell and F#, the prior more so. After some googling around I could not find a benchmark comparison of the more prominent functional ...
21
votes
3answers
5k views

What are the advantages of Scala's companion objects vs static methods?

Scala has no static-keyword, but instead has similar functionality through companion objects. Behind the scenes the companion objects are compiled to classes that have static methods, so all this is ...
7
votes
2answers
1k views

Decision for Unchecked Exceptions in Scala

As a java programmer, I have always been critical of Unchecked Exceptions. Mostly programmers use it as an en-route to coding easiness only to create trouble later. Also the programs (though untidy) ...
0
votes
1answer
189 views

The idea of functionN in Scala / Functionaljava

From brain driven development It turns out, that every Function you’ll ever define in Scala, will become an instance of an Implementation which will feature a certain Function Trait. ...
12
votes
1answer
980 views

Scala as a language for Generic Programming

In the paper “An Extended Comparative Study of Language Support for Generic Programming” by Garcia et al. an interesting comparison of programming languages features for generic programming is given: ...
3
votes
2answers
554 views

null values vs “empty” singleton for optional fields

First of all I'm developing a parser for an XML-based format for 3D graphics called XGL. But this question can be applied to any situation when you have fields in your class that are optional i.e. the ...
5
votes
1answer
379 views

Why do generics in Scala have erased types, and are not reifiable?

Why do generics in Scala have erased types, and are not reifiable? Is it due to lack of support from the JVM or for compatibility with Java libraries? What are the advantages in general of having ...
6
votes
5answers
2k views

What is a good use case for scala? [closed]

In a current project we have setup the build so that we could mix Java and Scala. I would like to use more Scala in our code base to make the code more readable and concise. In the process also learn ...
2
votes
1answer
2k views

Play 2 with Scala or Java? [closed]

I want to develop a big personal project using Play 2 Framework. I am expert with Java language but it seems, with the few articles I read that Play 2 works perfectly and especially with Scala. I've ...
6
votes
3answers
491 views

Functional Methods on Collections

I'm learning Scala and am a little bewildered by all the methods (higher-order functions) available on the collections. Which ones produce more results than the original collection, which ones ...
5
votes
1answer
522 views

Can Scala be considered a functional superset of Java?

Apart from the differences in syntax, can Scala be considered a superset of Java that adds the functional paradigm to the object-oriented paradigm? Or are there any major features in Java for which ...
4
votes
1answer
429 views

Constraints while designing the Java generics

Java generics look quite different from those available in Scala, although both were designed by Martin Odersky. From my point of view, the design of generics in Java is worse, for instance: there ...
7
votes
1answer
2k views

Why does Scala require functions to have explicit return type?

I recently began learning to program in Scala, and it's been fun so far. I really like the ability to declare functions within another function which just seems to intuitive thing to do. One pet ...
3
votes
1answer
198 views

How to read Scala code with lots of implicits?

Consider the following code fragment (adapted from http://stackoverflow.com/a/12265946/1333025): // Using scalaz 6 import scalaz._, Scalaz._ object Example extends App { case class Container(i: ...
8
votes
9answers
2k views

OS choice for functional developing

I'm mainly a .NET developer so I normaly use Windows/VisualStudio (that means: I'm spoiled) but I'm enjoying Haskell and other (mostly functional) languagues in my spare time. Now for Haskell the ...
2
votes
2answers
309 views

Case Class naming convention

In my recent adventures in Scala, I've found case classes to be a really nice alternative to enums when I need to include a bit of logic or several values with them. I often find myself writing ...
24
votes
6answers
3k views

How do you encode Algebraic Data Types in a C#- or Java-like language?

There are some problems which are easily solved by Algebraic Data Types, for example a List type can be very succinctly expressed as: data ConsList a = Empty | ConsCell a (ConsList a) consmap f ...
25
votes
4answers
4k views

What limitations does the JVM impose on tail-call optimization

Clojure does not perform tail call optimization on its own: when you have a tail recursive function and you want to have it optimized, you have to use the special form recur. Similarly, if you have ...
1
vote
2answers
968 views

Performance of concurrent software on multicore processors [closed]

Recently I have often read that, since the trend is to build processors with multiple cores, it will be increasingly important to have programming languages that support concurrent and parallel ...
8
votes
4answers
746 views

scalablity of Scala over Java

I read an article that says Scala handles concurrency better than Java. http://www.theserverside.com/feature/Solving-the-Scalability-Paradox-with-Scala-Clojure-and-Groovy ...the scalability ...
12
votes
3answers
766 views

Historical origins of Scala implicits

Scala has been called complex with its rich feature set by many of my colleagues and some even blamed all those new features of it. While most programmers are aware of the OO-features, and at least ...
11
votes
3answers
1k views

Scala or Clojure Functional Programming best practices

I did a lot of self-study coding, got some experience with Parallel Programming Models: Actors, Software Transactional Memory, Data Flow. When I am trying to apply these architectures to real life - ...
2
votes
1answer
2k views

A sample build.sbt to allow me easily specify source dirs and libraries?

I recently started learning Android development and I decided to follow the following development processes: Preinstall Scala in emulator Edit source files in IntelliJ IDEA 11 Compile the project ...
5
votes
6answers
370 views

Do non-pure interpreters still make the guarantees of functional programming?

I am assuming the implementations/compilers/generated C code (referred to hereinafter as generic, 'interpreter') for most functional programming languages are written in non-pure functional languages. ...
6
votes
3answers
3k views

Actor library / framework for C++ [closed]

In the C++ project I am working on, we have an application consisting of several processes deployed on different machines. This network of processes is dynamic since processes (clients or background ...
8
votes
4answers
694 views

Design in “mixed” languages: object oriented design or functional programming?

In the past few years, the languages I like to use are becoming more and more "functional". I now use languages that are a sort of "hybrid": C#, F#, Scala. I like to design my application using ...
6
votes
2answers
3k views

Migrating from Python to Scala wise when a lot of work is already done in Python?

Me and my friend are developing a web-app in Python + Flask + PostgreSQL. We have been working on it for the past few months and have developed a lot of schema/use-cases specific to Python + Flask + ...
1
vote
1answer
464 views

What are the benefits of using both Scalate and Jade?

I recently did a little "tool roundup": If I were to program a website in Scala and Coffeescript, what frameworks would I go for? I came across this great presentation: ...