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Dart Is Not the Language You Think It Is
An anonymous reader writes "Seth Ladd has an excellent write-up of Dart: 'When Dart was originally launched, many developers mistook it for some sort of Java clone. In truth, Dart is inspired by a range of languages such as Smalltalk, Strongtalk, Erlang, C#, and JavaScript. Get past the semicolons and curly braces, and you'll see a terse language without ceremony. ... Dart understands that sometimes you just don’t feel like appeasing a ceremonial type checker. Dart’s inclusion of an optional type system means you can use type annotations when you want, or use dynamic when that’s easier. For example, you can explore a new idea without having to first think about type hierarchies. Just experiment and use var for your types. Once the idea is tested and you’re comfortable with the design, you can add type annotations."
Those people always bitch about and those no one uses.
Since I have yet to hear any complaints about Dart, I can only assume it's in the latter category and no one cares.
I've been doing this with comments since 1999 and it works great! Of course I still haven't gotten around to that final step of going back and adding all those comments but I love the flexibility!
Unless you like bugs, type-checking is a good thing. Lack of type enforcement encourages what -- lack of forethought?
not having heard of it, and thus never having any thoughts about it, and since you say it's NOT what I think it is (nothing), I guess Dart *is* something!
I've been following Dart on and off since it's announcement. I'm still a little skeptical of the language, but I'm a fan of what they want to do. Here are their basic goals:
There is a lot more to it than this, but it's sort of a beginning. The language still hasn't hit 1.0, so no one is seriously using it (as the language itself was seeing large changes up until recently). Google has not talked about anyone outside of the Dart team itself that is using Dart within Google (they are doing it, it's just not being talked about yet).
Since 1.0 is expected this summer, you probably won't see many people using it until that milestone is hit. Once 1.0 is hit, people will be more willing to create real products with it, so you can expect to see more about Dart after that. As well, once the DartVM makes its way into Chrome (which will happen sometime after 1.0), you'll probably see a lot of press about the first Google App that is written in Dart.
It's still early in Dart's life. The only people really seriously using it are people that like learning new languages. Companies and most developers won't touch an in-progress programming language out of fear that syntax and behavior changes will screw them up.
Its not what it is, its something else.
No, nothing like Lisp.
Get ready to hear some bitching about Dart on this thread, then review your assumption.
I vote for no one cares.
I for one never encountered a situation where I thought "gee, if only I could prototype without types!". Types matter. When solving even the most basic data processing problem there's "input" and "output". Specifications are very clear on the formatting and types. What happens in between is dictated by those types.
Typeless programming in shorthand for lazy markup.
Or so that was my first thought. Then I got to the end of the article
Dart compiles to JavaScript and runs across the modern web
And suddenly I find it potentially very useful. I have a NodeJS project to develop a Streaming Service later this week. While I was planning on writing it in Coffeescript, the classic OO nature of Dart with Type Checking and Interfaces(!) seems like a potentially better match since the NodeJS app will be a clustered streaming service -- just the sort of application whose architecture could greatly benefit from these language features. If that succeeds, I know of a large retailer wanting to create a NodeJS middleware as a REST API to legacy systems, who might find Dart as compelling as I do.
Turing complete?
I fooled around with Dart a few months ago. I like the language. But I really want to be able to use it AND all the javascript libraries that do lots of work for me. It's my opinion that it will be hard for Dart to get traction if all those libraries have to be rewritten.
Dart understands that sometimes you just don’t feel like appeasing a ceremonial type checker.
Given that in Dard, the type checker is only ceremonial as far as I can tell, this is an interesting choice of words. The purpose of a true type checker like you find in Haskell, Agda, ML, ATS, etc. isn't just ceremonial. It guarentees certain properties of the resulting program (e.g., that variables of a certain type actually contain an object of that type, that you can never apply an invalid operation to an object, etc.). That is far from ceremonial.
Isn't that just Visual Basic 6, VBScript, JScript, ActionScript, Real Basic, Jabaco, or JavaScript/ECMAScript? There are languages out there and even C# has the dreaded 'var' in it as well. I just don't see Dart's use outside of Google products.
You say things that offend me and I can deal with it. Can you?
Being killed off is better than the alternative -- forced integration with google+. Will they require you to login to google+ to run the javascript transpiler? Will they auto-post your error log to your google+ page? Will they remove the "+" operator (like they did with search)? Who knows!
Do you even lift?
These aren't the 'roids you're looking for.
I haven't used DART yet, so I will not comment on the strength or the weakness of it
But, all through the decades that I've been in the scene, there have been so many programming languages invented, but so few of them being used
Some of the more widely used programming languages like C, for instance, are not perfect, but they are being used partly because of legacy, partly because of momentum, and partly because of the laziness of programmers to learn new, more useful languages
Talking about legacy, the other day there was a piece on Cobol, and that IBM is trying to extend Cobol to the cloudsphere
As for the languages that are not so-widely used, some of them are downright weird, but then, there are gems among them. The only downside for those few gems is that the ecology is not there to enable those few gems to become more widespread
I guess it's kinda Darwinian game plan --- not all surviving/thriving species are perfect, and not all the extinct species are bad, either
Muchas Gracias, Señor Edward Snowden !
more restrictions and unnecessary syntax
I like syntax. It helps human beings read code. It was never intended for anything else.
BTW, what language is going to evolve back to Lisp and be usable for writing OS kernels, drivers and other such primitives?
I was going to say BitC but that language evolved away from s-expressions to something more Haskelly.
That's what I think. ActionScript allows the same static/dynamic switch:
for(var i:int = 0; i < 0; ++i) { }
for(var i = 0; i < 0; ++i) { }
But, in strict mode, it will give you warnings for the 2nd.
The G
I'll support it. Javascript is a thoroughly horrible language with anachronistic syntax that requires specialised skills to understand. If Dart has the potential to rid my life of Javascript, please Google .. get it out there!!
I'm not sure why you were modded Troll. I tend to agree. Types are no good if they are not enforced. Either use a language that doesn't enforce typing or use one that does. This in between approach is indeed lazy.
One Problem is teaching.
One problem is "compatibility" or "easy to learn". E.G. regarding keywords.
C has a keyword: static.
C++ has the same keyword: static.
As Java aimed to be similar to C++ and "easy to learn" it also has a keyword static.
While the meaning of the "keyword" in Java and C++ is the same, it differs from C. (Oh! and this already is not true as you can use 'static' in C++ similar to C if you just use it for free functions and data).
So what does 'static' mean?
http://dictionary.reference.com/browse/static
http://www.thefreedictionary.com/static
http://www.merriam-webster.com/dictionary/static
http://oxforddictionaries.com/definition/english/static
Unfortunately 'static' in a programming language has no meaning at all. Why is the "starting method" in Java called "static void main(String[] args) {}"? Yeah, because in C and C++ it is called main(). Pascal has not that problem.
What do you think a non native english (oh, well what about the english?) considers if he hears the word 'static'?
Good, now lets bash Python and Groovy. What is a "def"? Oh? A definition? Are you certain you can distinguish what the difference between a definition and a declaration is?
So "methods" are now "declared" (or is it defined?) by the introducing keyword "def"? Oh, for fuck sake, I got it wrong again.
Oki, in Python you declare, oh no!!!! you define methods with the keyword "def". In Groovy you define variables (oh! no!!!!! you declare!!!) with the keyword "def".
Yeah, I could rant forever ...
All new languages we see here and there are only languages for programmers that already can program.
But, what is about expressing your mind?
What about teaching programming? Imho Java is one of the most difficult languages to teach. Why? Because you need to know already so much about programming to grasp it!!!!! (Same for C# ofc).
However: modern times show: you don't need to understand Java/C# (just a replacement for most modern languages) because the programing tasks a modern developer has (especially compared to the tools he has at hand) is so mondane. C++ on the other hand only shows how super smart and knowing you need to be to use the language, or not to shoot into your foot.
So where are we?
New languages should use new keywords, that describe precisely what they mean. No void, no static, no final or for that matter finally, no fucking def, var or func. Did I forget one? I certainly did. And they should have reasonable defaults. I hate Java meanwhile, "public void doit() {}", "private boolean done = false". Then we get to "static final String DID_WE_DO_IT = "yes we did";" What is so hard in having methods be PUBLIC by DEFAULT and attributes PRIVATE by DEFAULT? ... neither C++ nor Java nor C#. The redundancy hurts me literally.
Writing code is still possible, even if it hurts my hands and my eyes. But reading? I simply don't want to read code anymore
In a typical Eclipse window I would estimate 30% of all characters/words are simply superfluous. And the fact that they all have a different colour emphasizes this.
How would a real world language look to you if it was written like this: "I want (that is me the guy writing) that we (that is us, you who are listening, and me who is talking) that we (well, dont be mistaken, I only want it, it is not an order) that we (yes, I invite you to participate) go to the beach (and want does not mean it is super important ... it is kinda void)? (And all words in () above in a different colour? Like pink (ARRRRGGG!!!!) light green ( /*facepalm*/), dark and light blue, emphazised(bold) full
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
Yeah, exactly. What the writeup calls "appeasing a ceremonial type checker" is more properly called "debugging".
Don't get me wrong, I like the thrill of the chase, the satisfaction of tracking down a really hard bug, as much as anyone. But I like programming even more. Using a well-designed type checker, I can find bugs in my program and convince myself that I'm programming rather than debugging.
sub f{($f)=@_;print"$f(q{$f});";}f(q{sub f{($f)=@_;print"$f(q{$f});";}f});
I can confirm that. The keys are still where they ment to be. However if you use Emacs you are likely assuming that this is a nice editor. Well, as far as I can tell it is a nice operating system, but it lacks a decent editor. Honestly you should give vi or vim a try.
No offense, only a full hearted wish for your future!
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
For those of you who don't know, asm.js is a subset of JavaScript that's meant to be easy to compile. In other words if you use asm.js the code your will work in all browsers, but should run faster in some. In that FAQ they say their compiled asm.js runs at about 1/2 the speed of C, making it roughly twice as fast as JavaScript V8.
Which is wonderful, except that JavaScirpt is a prick of a language, and so I'd imagine that asm.js is a tedious, prick of a language. But Dart compiled to asm.js - sounds like a marriage made in heaven.
Wait a minute. I'm a programmer BECAUSE I'm lazy.
Return a list from a function. Sure, you can legally do it, there's nothing in the language inherently stopping you, but experienced C programmers will avoid returning a list at all costs, because suddenly you have to care about whether the caller frees the list properly, and what if the things in the list are used elsewhere and we need to do reference counting etc.. etc... I've worked on a C codebase that was a couple hundred thousand lines of code, and I can't think of anywhere that we ever returned a list from a function. I can't think of any Haskell program more sophisticated than "hello world" that I didn't use "map" and other list functions all the time.
Ultimately, the cost of manual memory allocation isn't just the extra work you have to do to make sure you aren't leaking or corrupting memory, it's the algorithms you won't allow yourself to even consider because the memory management would just be too hard.
I'm not saying C doesn't have it's place, I'm just saying that there are software engineering costs associated with using C as opposed to a higher-level language.
And then there's Python.
people bitch about python. at least I do.
whitespace has effect. who has time for that..
world was created 5 seconds before this post as it is.
And then there's Python.
people bitch about python. at least I do.
whitespace has effect. who has time for that..
Same, but it's almost my only complaint. Other than that it's an elegant language, my favorite for scripting.
XML is a known as a key material required to create SMD: Software of Mass Destruction
Yeah, exactly. What the writeup calls "appeasing a ceremonial type checker" is more properly called "debugging".
Don't get me wrong, I like the thrill of the chase, the satisfaction of tracking down a really hard bug, as much as anyone. But I like programming even more. Using a well-designed type checker, I can find bugs in my program and convince myself that I'm programming rather than debugging.
Agreed. The languages I've used the most would be Smalltalk, C++, Javascript and Java (in rough chronological order, some overlaps), two are weak typed two are strong typed.
After a day grinding out hundreds of lines of productive Java trying to do anything in javascript just makes me want to drown kittens... well perhaps kittens named Brandon Eich. (Sorry Brandon... I've just seen too many sins committed with your language.)
XML is a known as a key material required to create SMD: Software of Mass Destruction
Return a list from a function. Sure, you can legally do it, there's nothing in the language inherently stopping you, but experienced C programmers will avoid returning a list at all costs.
Hmm, that's odd. So C has its place but it's avoided because it lacks garbage collection? My C code has automatic garbage collection and OOP facilities. It's got lists and maps, and a comprehensive collections library. It's just under 30 thousand lines of code, but then it's just a game engine. It only has to do everything the computer actually can. If you don't have these basic facilities in your C library, it's your own damn fault. Seems to me if I want I can always have it in C, there's no excuse for not having it.
My memory manager replaces the malloc / free facilities, so it can even be added to other C code-bases, hell, I use it in C++ code because it's faster than the GC in the standard library (for the way I use it). So it's not like I have to call reference counting functions; Just the GC_recycle() function, or enable it to run automatically, which blocks on malloc() / free(), and optionally gives each thread their own local GC rather than a unified approach such that part of the program can garbage collect while another keeps running.
However, when my testers bitch about stutter in Java / Android No matter how badly I want Java or JavaScript to give me control of the damn garbage collector, so it doesn't run in the middle of the rendering loop or intense action sequence, I can't have it. I have to implement an object cache atop Java and pre-allocate everything, try my hardest not to give the GC a chance to run, and if I slip up once and let that fucker have control, it's game over, literally, when the enemy attacks and the game lags for half a second.
I return lists from functions all the time you dumbass. I'm an "experienced C programmer". Stop painting with such a wide brush, you're getting the paint in you eyes.
An AC adds:
Or return a function from a function?
I throw Function pointers around like crazy, that's how efficient state machines, decision trees, or other flexible structures are formed. Hell, my Entity-like system allows Actors to composite sets of functionality as it transitions states to create efficient AI -- Just because it's fleeing doesn't mean it's still not searching for Health. It would be like if C++ let you pick which methods you inherited from multiple parents on the fly. I mean hell, returning and passing a function pointer is how I implemented multiple sorts:
// or
list->sort( list, list->getSortRoutine( SORT_MERGE ) );
myCustomRoutine = getCurrentSort();
list->sort( list, myCustomRoutine );
That first "list" being passed in the sort function pointer invocation is where your magic "this" pointer comes from in C++.
You could write your own garbage collector for the JVM, which gives you 100% control over when, where and how to GC.
Sometimes the type system gives more overhead than safety. A wonderful satirical example in Java: https://github.com/Mikkeren/FizzBuzzEnterpriseEdition
/* actual code I want to test */ } " and either put Imports at the top or use fully qualified package names. So the equivalent "fast try something out" I do with Python still takes four times as long.
You also have to weigh developer feedback time. I've developed web applications with Java Struts, coding directly to the Java Servlet API, Play Framework 1.x, and Play Framework 2.x (in Java, not Scala), and Python with Twistd. In order of speed of development of correct (i.e. in production without known bugs) code, they are from fastest to slowest: Python with Twistd, Play 1.x, Play Framework 2.x, Java with the Servlet API, Java Struts. Play Framework 1.x and Python give you instant reload. You save your changes, hit F5 in your browser, and see your change immediately. Anything I built without that takes three times as long. Play Framework 2.x doesn't have it, because under the hood Play 2 uses Scala and at least on my machine, best-case-scenario a Scala recompile of modified files after I change some Java file takes 5+ seconds. With Struts and just using the Servlet API, I have to reload the damn application and that's 10 seconds or longer. It seems like a trivial thing, but it's huge.
I'd say hot reload brings Java on par with Python for development, except Python has one extra feature: the REPL. "How does X work?" type.. "Oh, that's how it works", go back to coding. With Java, even in an IDE it's "create a public static void main (String [] args) throws Exception {
There's a reason that Google and Facebook and Twitter all use C++ and Java behind the scenes. But there's also a reason millions of sites use PHP, Python, Ruby, and Perl up front - because the development speed is so fast that you're into your testing (and unit tests) in a third the time of the Java version. So if your Java build takes three weeks of coding the application and one week of coding the tests, and your scripting language version takes one week of coding the application and two weeks of coding the tests (to offset the weaker type system), you still get to market faster with the scripting language.
Maybe the ideal is something like Perl6 (which has optional typing but does enforce type constraints when they're listed) or Groovy (which you can convert to Java more or less as-is once your rapid development phase is over).
I want to se your C code for this simple Haskell function:
f x y = x*y
When applied to just one argument:
g = f 5
You get back an one argument function that will multiply by 5:
g 4 equals 20.
h = f 10
h 4 equals 40.
Your task is to write a C function, that does not memory leak (although it is hard enough even if you are allowed to leak), that based on some parameter will return a another function that is different each time. Like in the above Haskell code, I shall be able to invoke your C function multiple times, for example with the values 5 and 10 and get back new functions that will multiply with 5 and 10. The later must of course not override the behaviour of the former.