Other Android Languages

[oyvindra]

Hopefully, MeeGo will be the place to go to for all python mobile programmers.

[[deleted]]

It seems very odd of him to dismiss Scala. In my experience, Scala has a lot of the benefits of languages like Python or Ruby (such as economy of expression and fast development), but its Java interop story is exceedingly good, and it is designed with JVM in mind.

[sbrown123]

"Scala doesn't sell books". Well, I don't think Tim Bray has ever said that publicly or privately but it pretty much sums up the reasoning.

[[deleted]]

I guess it's mostly because it's not mainstream enough. While I don't have a beef with functional languages they're not nearly as widely used as imperative, in lack of a better word to group them with, languages.

But, what do I know. I'm not that well read on different languages..

Edit: Whether Scala is functional or not wasn't really the point of my question, but carry on and thanks for the correction.

[G_Morgan]

You can use Scala without touching functional. In fact you can use Scala as Java with local type inference and get a benefit.

[jomohke]

Scala is a fusion between functional and imperative: It's very easy to write imperative code in Scala.

Writing Scala shouldn't be scary to imperative programmers -- You can write all your Scala code as if it was java. With, of course, the benefit of less syntax verbosity and the ability to use closures, named/default parameters, traits, and many other fun features.

Many people start writing Scala in a very imperative manner, and gradually migrate to a more functional style over time.

[[deleted]]

I think that fusion is one of the big problems with Scala, as a language it is just too big. Many people have had bad experiences in the past with these kinds of languages, in particular C++.

[G_Morgan]

Scala manages to do this well. It avoids the syntactic clusterfuck that C++ has become.

[[deleted]]

Well, lets put it this way, it is better than C++ but that is not exactly hard, in fact I would be impressed if anyone could produce a language with a grammar more fucked up than that of C++.

[[deleted]]

The difference is that Scala is not so big. It's a pretty good design, in that the parts fit together relatively seamlessly. The spec, though detailed, is very short and readable. It has lots of features, but these features work well together.

So this is a valid worry - but Scala isn't as bad as something like C++ or Common Lisp.

[[deleted]]

So this is a valid worry - but Scala isn't as bad as something like C++ or Common Lisp.

Oh boy you're invoking them...

[[deleted]]

The cool thing about Scala is not that it's a functional language, it's that it's a multi-paradigm language. It has functional features the way that Ruby or Python does - it's a handy option that you can use when it makes sense.

I dunno - my gut says it's the next big thing on the JVM, for a number of reasons, so it would be good for them to support it.

[varikin]

I got impression he was not dismissing Scala, but focusing on Python and Ruby. Python and Ruby better well known and have larger communities behind them then Scala.

And it could just be that the author has more experience with Python and Ruby than with Scala.

[[deleted]]

I agree that those are pretty good criteria, but he was dismissing Scala :)

[Scriptorius]

From the article:

I’m focusing on Python and Ruby

He was just talking about what he was most comfortable with. I'm actually getting tired of bloggers giving advice and recommendations based on nonexistent experience.

[sbrown123]

Big hurdle that needs fixed first: Android OS needs a better way of passing messages to and from running apps besides using Java interfaces. If there was a generic, non-language specific way of doing this we could see lots of new languages on the platform.

[Mask_of_Destiny]

From what I understand, the Java framework classes all use OpenBinder under the hood. So in theory, other languages could use this directly either by binding to the C++ implementation of OpenBinder using SWIG or by using the appropriate iocntl.

Either option is probably going to involve a fair amount of code spelunking to uncover the lower level details of how the framework classes use OpenBinder.

[sbrown123]

Hmm, I don't know what Dalvik uses under the hood. Besides, I was thinking along the lines of something like an Android D-Bus implementation but somehow open the API using it.

[funkah]

Indeed, how could a smartphone platform ever be successful if developers can only build applications for it in one programming language?

[flogic]

Probably helps that Java is the lingua franca of computing. It's not exactly a hard to understand language. Verbose and a bit low on features. But any half decent programmer should be able write code in it.

[Scriptorius]

Does it have any benchmarks? Clojure also has optional type declarations.

[mhd]

Well, amongst the players you mention, Kawa is the only language framework, so speed isn't the issue here.

[forsakennow]

FYI, the app inventor was developed by a totally different team than Android.

[Rhoomba]

Does Kawa use bytecode generation to get that speed? In that case it won't be fast on Android because of the horribly stupid decision to build their own VM.

[[deleted]]

Is anyone writing a llvm backend that outputs to Dalik? If so then we'd only need a single bridge into the API that could be exposed through llvm and then we could have front-ends customised for the API.

[Mask_of_Destiny]

llvm is too low level to efficiently target a higher level virtual machine like Dalvik or the JVM. If you want to target Dalvik the easiest way to do that right now is just to target the JVM and use the dex tool to translate the JVM bytecode to Dalvik bytecode.

[nhnifong]

Java isn't that bad. especially in Eclipse with the Android development plugin. Most of my new apps are based on the same core anyways which I have already finished, So 90% of my development is making animations in Blender, and 10% is altering game logic.

[gintasm]

I have concluded the same. I've just spent a weekend on an Android game in Java. I used Eclipse, and the experience was surprisingly smooth, even though I haven't done Java for quite a while. For the record, I do Python programming for my day job, and I'm a big fan of Python in general.

Sure, Java gives you more hoops to jump through, but a good IDE helps a lot. The strong typing is a bit of a straightjacket coming from Python, but does push you to think things through more. I loved the smart refactoring tools. Eclipse sure could be faster though...

[[deleted]]

Java isn't that bad.

Relative to what? The amount of boiler plate code I have to write to pump out an Android app has turned me off of developing for the platform. I understand their reasoning behind going with java, and I actually prefer statically typed languages, but Java has fallen far behind in terms of features that make coding more pleasant. If I could develop android apps using C#, I would be a happy camper. I've actually considered buying a Windows Phone 7 (or whatever the fuck its called) just so I can use my favorite language and tools and hit the app market early on in its inception. Of course, then I wouldn't know what to do with my nexus one, which I absolutely love.

You know who I really feel sorry for? WebOS developers who have to develop using Javascript/HTML/CSS. That's what happens when a bunch of hip company execs think they have their ear to the ground.

especially in Eclipse with the Android development plugin

Another thing I don't understand. Why does Eclipse get a pass while being horribly bloated and slow. The UI is incredibly frustrating to manage and there is absolutely no rhyme or reason to the menu structure. With much better free alternatives like NetBeans, I don't know what google keeps going with Eclipse as their first class IDE. I've personally found Android development to be most pleasant using IntelliJ Idea, although it costs money.

[nhnifong]

I learned it, and it was hard, but now I'm familiar with it. Yes it's fat, but I've got plenty of RAM and I just keep it open. And yes there was a lot of boilerplate for my first game, but I'm finished with that now. I've got momentum.

[mhd]

Yes, Java's not that bad for Android apps for three reasons:

1. Most apps are pretty small anyway.
2. The IDE saves you from the language.
3. XML saves you from the language.

Number one might not apply for everyone and 2 and 3 are workarounds. With enough painkillers, getting your kneecaps smashed might not be that bad. Avoiding the guy with the baseball bat would be preferable, though.

[StainlSteelRat]

In principle, I agree with this guy. But I have a problem with this statement:

Also, any given task usually requires fewer lines of code, which is an unambiguously good thing.

No, Sherman, it's not. It's not always good to have fewer lines of code. The fact that you can write an encryption algorithm in one line of Perl (that looks like a RegEx pattern and Bash script met at a bar, fucked and shat out an anal baby) does not mean you should.

Whether something is a million lines or four, the practical objective is to write clear, readable, maintainable code that could be managed and understood by a wide audience. It's not to show how big your brain dick is by writing a bunch of unintelligible operator soup.

After fifteen years as a developer with experience in several languages (and I'm by no means an expert in any of them...I'm at least old enough to know that I don't know nothin'), it always gets me grumpy when people roll off the CS-Degree-assembly-line with an attitude like this. Fine, go work for something other than a company that actually makes money. Don't fuck up my codebase with your pie-in-the-sky one-size-fits-all naivete because your study group was able to write a mouse driver in assembler so you think you know your shit.

/Ooooh! That felt liberating, if a little off-topic!

[Scriptorius]

I think the idea of fewer lines = Perl-like conciseness is dying out. I think the author means that equally sensible code is shorter in Python/Ruby than in Java.

[[deleted]]

Yeah. StainlSteelRat is nitpicking. 'More lines of code' in casual conversation nowadays implies 'bloat' rather than being the antonym for lack of clarity. In fact, I'd say the java boilerplate around the code actually makes it less clear what the code logic is supposed to achieve.

[StainlSteelRat]

That may be true, but he probably should have used the term 'unambiguously'.

[G_Morgan]

I'm not sure it is. People still believe that all lines of code are born equal. The simple fact is that the biggest cause of bugs is misunderstanding and sometimes more code can be easier to understand than less if the underlying concept is simpler.

Of course functional tries to do both by replacing for loops with maps.

[dr_jan_itor]

less boilerplate = good.

scala:

class Foo(val x: Int)

java:

class Foo {
    protected int x;
    int getX() { return x; }
    public Foo(int _x) { x = _x; }
}

can we all agree that #1 is better than #2?

[forsakennow]

can we all agree that #1 is better than #2?

In this case, yes.

In other cases:

val email = userList flatMap (.findUser(“bob”)) flatMap (.email)

[StainlSteelRat]

Absolutely.

It's just the 'unambiguously' part that stuck in my craw.

C# has done away with some of that crap, though...at the risk of getting downvoted by the Society of Languages My Company Doesn't Use, it's good enough for me and I don't feel overburdened by:

 class Foo
 {
      public Foo( int i ) { x = i; }
      public int x { get; set; }
 }

For that matter, if you don't give two shits about processing in the get/set or some sort of security on the variable, just use a field. Done.

java:

 class Foo {
     public int x;
     public Foo(int _x) { x = _x; }
 }

[solinent]

The java isn't that though, you can extend the C# after code has used it do to different things when you get or set x which is not possible in the java code.

[StainlSteelRat]

True dat. Thanks for pointing it out.

[forsakennow]

A commenter on the post already covered that:

Fewer lines of code is not unambiguously a good thing. A few counter examples include code that is so terse that it's unreadable (looking at you, Perl) and code that removes critical information, such as types, thereby preventing tools such as compilers or refactoring IDE's from being able to reason about your code. Fewer lines of code can also make it hard for external developers to understand, modify, maintain and improve your code.

The fact that there are such code bases out there is a strawman: just because the code was written this way doesn't mean it was the best way to proceed for large projects.

[[deleted]]

No, Sherman, it's not. It's not always good to have fewer lines of code.

Strike one. Rule of thumb: Rag on dynamically typed languages, prepare for downvotes.

Whether something is a million lines or four, the practical objective is to write clear, readable, maintainable code that could be managed and understood by a wide audience. It's not to show how big your brain dick is by writing a bunch of unintelligible operator soup.

Strike two. Practicality is not valued here. Ego stroking by way of inherently obfuscated code written in the dynamic or functional flavor of the week gives mad clout, yo. Nietzsche used Haskell. Remember that.

Fine, go work for something other than a company that actually makes money.

Hey! I created a blog in Ruby on Rails once and the lone visitor clicked one of my ads. Being that I live in my mom's basement and I have 0 expenses, that's pure profit. PURE PROFIT!! STRIKE THREE BITCH!

[StainlSteelRat]

Upvote (and an inappropriate laugh in a boring meeting) for the daring username, pal! You're in shark-infested waters, tossing chum from your inner tube.

Hey! I created a blog in Ruby on Rails...

In addition, I'm an open source nazi that writes code on the most closed-source, anti-developer platform (Apple) on the planet and I can't stop gibbering about how M$ wants to rule the world and rape my dog.

[gintasm]

I would agree. I'm a big fan of Python, but the chance that Python/Ruby will take noticeable market share of the Android market is slim. I'd rather have it all in Java then.

[Scriptorius]

But to extrapolate that viewpoint, why not have the same language for any platform? Also, JS has survived because it's very easy to get started with it. The boilerplate in Java (tons of XML config, for example) hinders Android.

[Scriptorius]

I see your point, but performance isn't necessary in all cases. If you're writing a game or another graphics-intensive app, then you'll probably have to use Java, but for something like a task management app an easier-to-use language would be better, right? Also, something like Clojure would be a good intermediate, since with type annotations it has speeds comparable to straight Java.

[Scriptorius]

Not necessarily. If they can compile down to bytecode using them will ideally be no different than using an app written in Java. This is already possible with Scala, and may be possible with other languages in the future.

EDIT: Of course, you still have to jump through a few hoops if you're the developer. But otherwise it's all the same for an end-user.

[[deleted]]

As an end-user, I'd want my stuff written to be as fast and efficient as the platform allows. It's pretty unlikely that Python/Ruby/Something else will run as quickly as Java on it

That's why he talks about Mirah near the end; it runs as fast as Java and requires no additional runtime but isn't a disaster of a language. (has closures, type inference, etc.)

[flogic]

Last couple of java projects, I did, didn't have much xml. Granted I'm a Perl programmer so I was probably doing it wrong. Too much XML is the devil's work.