View mode: basic / threaded / horizontal-split · Log in · Help
February 17, 2013
Java binaries
Would it ever be possible to compile D source directly to java to 
take advantage of what java offers. (e.g., the ability to run d 
code inside a browser)

I'm not talking about necessarily fully fledged 
functionality(obviously stuff like asm isn't going to work) but 
basically the ability to use D's syntax and some of it's compiler 
features(mixins, templates, etc).
February 17, 2013
Re: Java binaries
On 2/16/2013 7:26 PM, js.mdnq wrote:
> Would it ever be possible to compile D source directly to java to take advantage
> of what java offers. (e.g., the ability to run d code inside a browser)
>
> I'm not talking about necessarily fully fledged functionality(obviously stuff
> like asm isn't going to work) but basically the ability to use D's syntax and
> some of it's compiler features(mixins, templates, etc).
>

Java doesn't have pointers, so right off the bat there'd be big problems.
February 17, 2013
Re: Java binaries
On Sunday, 17 February 2013 at 07:53:15 UTC, Walter Bright wrote:
> On 2/16/2013 7:26 PM, js.mdnq wrote:
>> Would it ever be possible to compile D source directly to java 
>> to take advantage
>> of what java offers. (e.g., the ability to run d code inside a 
>> browser)
>>
>> I'm not talking about necessarily fully fledged 
>> functionality(obviously stuff
>> like asm isn't going to work) but basically the ability to use 
>> D's syntax and
>> some of it's compiler features(mixins, templates, etc).
>>
>
> Java doesn't have pointers, so right off the bat there'd be big 
> problems.

Java does have pointers... you just can't get to them easily. At 
the very least, you could allocate and manage your own chunk of 
memory and do all the pointer arithmetic yourself on that chunk. 
This would require the chunk to be pinned in some way and the GC 
to be turned off but it is an option.

Also, have you looked much at sun.misc.Unsafe?

Or maybe one could use the JNI to write an external memory 
manager for each platform and all pointer arithmetic is passed 
through that. Of course, if one goes this far then any "javaD" 
would need to be able to work well with importing java libraries 
to be of any use.
February 17, 2013
Re: Java binaries
Sorry to come to this thread late, and apologies if I am missing the
real point to this thread.

On Sun, 2013-02-17 at 10:13 +0100, js.mdnq wrote:
> On Sunday, 17 February 2013 at 07:53:15 UTC, Walter Bright wrote:
> > On 2/16/2013 7:26 PM, js.mdnq wrote:
> >> Would it ever be possible to compile D source directly to java 
> >> to take advantage
> >> of what java offers. (e.g., the ability to run d code inside a 
> >> browser)

Running Java in the browser is now unlikely to ever happen again.  If
anything the target should be JavaScript or Dart, and even Dart would be
a huge risk.

> >> I'm not talking about necessarily fully fledged 
> >> functionality(obviously stuff
> >> like asm isn't going to work) but basically the ability to use 
> >> D's syntax and
> >> some of it's compiler features(mixins, templates, etc).

A lot of work is going into creating Python executability in browsers.
Skulpt, Brython, etc., but traction is minimal. Browsers mean HTML5 and
ECMAScript (aka JavaScript)

> >
> > Java doesn't have pointers, so right off the bat there'd be big 
> > problems.
> 
> Java does have pointers... you just can't get to them easily. At 
> the very least, you could allocate and manage your own chunk of 
> memory and do all the pointer arithmetic yourself on that chunk. 
> This would require the chunk to be pinned in some way and the GC 
> to be turned off but it is an option.

There is the possibility of using NIO2 buffers in ways that were never
envisaged. This is effectively what happened in RTSJ, which was a
real-time systems framework using Java and JVM. RTSJ sadly was too far
ahead of its time and so died. The last vestige will die when the Mars
Rover does.

> Also, have you looked much at sun.misc.Unsafe?

You really don't want to go there ;-)

Obviously for garbage collection and concurrency and parallelism control
you have to go there so as to subvert the JVM object model. The question
is that unless you are working on the G1 garbage collector or
java.util.concurrent primitives, is there any point?

> Or maybe one could use the JNI to write an external memory 
> manager for each platform and all pointer arithmetic is passed 
> through that. Of course, if one goes this far then any "javaD" 
> would need to be able to work well with importing java libraries 
> to be of any use.

Sounds like a mountain rather than a molehill. We are looking at
something vaguely analogous to get CUDA and OpenCL working from
GPars/Groovy/Java. Good for users, very ugly for implementors.

Unless there is a mapping of the semantics of a language to the
intermediate code of the platform, then it is better not to bash head on
wall but to go put energies into something more productive. If the D
semantics cannot be mapped down to the JVM bytecodes, then D is not a
language you want to run on the JVM. Given
Java/Scala/Kotlin/Ceylon/Groovy as the static languages and
Groovy/JRuby/Jython/Closure as the dynamic languages (yes Groovy is
correctly in both categories!) is there really a market for a minor
player native code language trying to ease itself onto the JVM platform?

The world is split into native code, PVM, JVM, JavaScript/ECMAScript. D
only really has a play in one of these, and needs to get real traction
there first before looking for new lands to conquer. Else it risks being
seen as a solution looking for a problem to solve.

-- 
Russel.
=============================================================================
Dr Russel Winder      t: +44 20 7585 2200   voip: sip:russel.winder@ekiga.net
41 Buckmaster Road    m: +44 7770 465 077   xmpp: russel@winder.org.uk
London SW11 1EN, UK   w: www.russel.org.uk  skype: russel_winder
February 17, 2013
Re: Java binaries
On Sunday, 17 February 2013 at 03:26:13 UTC, js.mdnq wrote:
> Would it ever be possible to compile D source directly to java 
> to take advantage of what java offers. (e.g., the ability to 
> run d code inside a browser)
>
> I'm not talking about necessarily fully fledged 
> functionality(obviously stuff like asm isn't going to work) but 
> basically the ability to use D's syntax and some of it's 
> compiler features(mixins, templates, etc).

depends on what you mean with "run inside a browser", I would use 
NaCl instead, if I wanted to run D in a browser, but of course it 
requires Chrome.

http://code.google.com/p/nativeclient/
February 17, 2013
Re: Java binaries
On 2/17/2013 1:46 AM, Russel Winder wrote:
> The world is split into native code, PVM, JVM, JavaScript/ECMAScript. D
> only really has a play in one of these, and needs to get real traction
> there first before looking for new lands to conquer. Else it risks being
> seen as a solution looking for a problem to solve.

I agree. There was at one time a D implementation on .net, but it suffered from 
.net's lack of support for pointers, which meant that slices performed poorly.
February 18, 2013
Re: Java binaries
On Sunday, 17 February 2013 at 09:47:08 UTC, Russel Winder wrote:
> Sorry to come to this thread late, and apologies if I am 
> missing the
> real point to this thread.
>
> On Sun, 2013-02-17 at 10:13 +0100, js.mdnq wrote:
>> On Sunday, 17 February 2013 at 07:53:15 UTC, Walter Bright 
>> wrote:
>> > On 2/16/2013 7:26 PM, js.mdnq wrote:
>> >> Would it ever be possible to compile D source directly to 
>> >> java to take advantage
>> >> of what java offers. (e.g., the ability to run d code 
>> >> inside a browser)
>
> Running Java in the browser is now unlikely to ever happen 
> again.  If
> anything the target should be JavaScript or Dart, and even Dart 
> would be
> a huge risk.
>
>> >> I'm not talking about necessarily fully fledged 
>> >> functionality(obviously stuff
>> >> like asm isn't going to work) but basically the ability to 
>> >> use D's syntax and
>> >> some of it's compiler features(mixins, templates, etc).
>
> A lot of work is going into creating Python executability in 
> browsers.
> Skulpt, Brython, etc., but traction is minimal. Browsers mean 
> HTML5 and
> ECMAScript (aka JavaScript)
>
>> >
>> > Java doesn't have pointers, so right off the bat there'd be 
>> > big problems.
>> 
>> Java does have pointers... you just can't get to them easily. 
>> At the very least, you could allocate and manage your own 
>> chunk of memory and do all the pointer arithmetic yourself on 
>> that chunk. This would require the chunk to be pinned in some 
>> way and the GC to be turned off but it is an option.
>
> There is the possibility of using NIO2 buffers in ways that 
> were never
> envisaged. This is effectively what happened in RTSJ, which was 
> a
> real-time systems framework using Java and JVM. RTSJ sadly was 
> too far
> ahead of its time and so died. The last vestige will die when 
> the Mars
> Rover does.
>
>> Also, have you looked much at sun.misc.Unsafe?
>
> You really don't want to go there ;-)
>
> Obviously for garbage collection and concurrency and 
> parallelism control
> you have to go there so as to subvert the JVM object model. The 
> question
> is that unless you are working on the G1 garbage collector or
> java.util.concurrent primitives, is there any point?
>
>> Or maybe one could use the JNI to write an external memory 
>> manager for each platform and all pointer arithmetic is passed 
>> through that. Of course, if one goes this far then any "javaD" 
>> would need to be able to work well with importing java 
>> libraries to be of any use.
>
> Sounds like a mountain rather than a molehill. We are looking at
> something vaguely analogous to get CUDA and OpenCL working from
> GPars/Groovy/Java. Good for users, very ugly for implementors.
>
> Unless there is a mapping of the semantics of a language to the
> intermediate code of the platform, then it is better not to 
> bash head on
> wall but to go put energies into something more productive. If 
> the D
> semantics cannot be mapped down to the JVM bytecodes, then D is 
> not a
> language you want to run on the JVM. Given
> Java/Scala/Kotlin/Ceylon/Groovy as the static languages and
> Groovy/JRuby/Jython/Closure as the dynamic languages (yes 
> Groovy is
> correctly in both categories!) is there really a market for a 
> minor
> player native code language trying to ease itself onto the JVM 
> platform?
>
> The world is split into native code, PVM, JVM, 
> JavaScript/ECMAScript. D
> only really has a play in one of these, and needs to get real 
> traction
> there first before looking for new lands to conquer. Else it 
> risks being
> seen as a solution looking for a problem to solve.

Everything started out as minor and if D's language features are 
truly good and D is as well designed as some think then people 
will migrate to it. Essentially "If you build it they will come" 
type of scenario.

Those that would use a D for java type of language can't so there 
is no way to measure how successful it would be.

Virtual machine programming has many benefits but we definitely 
do not need another one. Hence, it would be nice to leverage 
java, which already has build up it's user base to further the D 
language paradigm. I like D but so far it doesn't seem to be 
going anywhere. Why? Because one already has all these other 
languages and tools to do the job.

Imagine this:

Suppose with a snap of your fingers you could have the following 
products:

High stable and performant D compiler for all the major 
platforms(including many embedded) with a large collection of 
support tools.

A D virtual machine that runs on many platforms. A D for java 
compiler that compiles almost any D program into java bytecode 
and use java libraries.

etc...

Now, if you had all this stuff magically out there do you think 
that the userbase for D would explode? I do... In fact, it would 
happen for most decent languages. (of course, we could argue 
about the exact details but D would become a major player within 
a few years)

Hence, having this stuff is important for D's success. Of course, 
it may not be possible in some cases or sacrifices have to be 
made. In any case I'm not convinced that a D for java can't be 
implemented and I do feel it would further D's popularity.

Of course, D is still in it's infancy but it would be cool it 
someone was interested in trying to make a D for java and see 
where it goes. I think something useful would come out of it. 
(Please don't say I should do it either...)
February 18, 2013
Re: Future directions for D [was Re: Java binaries]
On Mon, 2013-02-18 at 03:37 +0100, js.mdnq wrote:
[…]
> Everything started out as minor and if D's language features are 
> truly good and D is as well designed as some think then people 
> will migrate to it. Essentially "If you build it they will come" 
> type of scenario.

D is out there, but not widely enough known, people are sticking with C
and C++ or heading to Go. And then there is Rust.

> Those that would use a D for java type of language can't so there 
> is no way to measure how successful it would be.

Very true. You can only get a feel for a reaction when the capability is
there. However look at the JVM-based milieu. Despite Groovy, Clojure,
Ceylon, Kotlin, JRuby, Jython, Scala, the vast majority of organizations
are Java fixated. Worse they are worrying about migration from Java 5 or
6 or 7, some even from Java 1.4. It is all to easy to forget from the
excitement of the bleeding edge how far behind most of the world is.

> Virtual machine programming has many benefits but we definitely 
> do not need another one. Hence, it would be nice to leverage 
> java, which already has build up it's user base to further the D 
> language paradigm. I like D but so far it doesn't seem to be 
> going anywhere. Why? Because one already has all these other 
> languages and tools to do the job.

I cannot see C, C++, D, Go, Rust, etc. ever working on the JVM enough to
compete with Java, Scala, Groovy, Ceylon, Kotlin which are designed for
the JVM. Creating a backend for D to sit on the JVM would be an
interesting academic project that might eventually lead to a product,
more likely it would make a great PhD.

D's lack of traction is mostly to do with it not making headway against
C and C++ in the C and C++ communities. Go is pitched against C, C++ and
Python and is beginning to make headway. It has two features that allow
this: use of CSP ( at least Rob Pike's variant developed in parallel)
for concurrency and parallelism, and the support of Google. D has actors
and data parallelism and a huge void for the number of big companies
standing up saying they are happily using D.

A couple of international banks have ditched large centralized Java
mindset for a combination of small Scala install for centralized and
Python out in the business units. This has been a huge fillip to both
Scala and Python. Not least that I am currently making  most of my
living from Python training for these organizations.

Who are the organizations using D as their strategic programming
language? Who are the companies offering D training? Where is the
plethora of books on the D language?

Getting high scores for posts on StackOverflow and Reddit actually mean
very little. A good rating on TIOBE matters more than it should. Having
training companies with stock training courses and big, high profile
users, is what really matters.

> Imagine this:
> 
> Suppose with a snap of your fingers you could have the following 
> products:
> 
> High stable and performant D compiler for all the major 
> platforms(including many embedded) with a large collection of 
> support tools.
> 
> A D virtual machine that runs on many platforms. A D for java 
> compiler that compiles almost any D program into java bytecode 
> and use java libraries.
> 
> etc...
> 
> Now, if you had all this stuff magically out there do you think 
> that the userbase for D would explode? I do... In fact, it would 
> happen for most decent languages. (of course, we could argue 
> about the exact details but D would become a major player within 
> a few years)
> 
> Hence, having this stuff is important for D's success. Of course, 
> it may not be possible in some cases or sacrifices have to be 
> made. In any case I'm not convinced that a D for java can't be 
> implemented and I do feel it would further D's popularity.

Mapping D to Java and then using a Java compiler is feasible but a huge
undertaking, more than trying to compile D to JVM bytecodes. But as soon
as anyone mentions JNI as an integral part of a language's
implementation, they are on to a loser. JNI needs to be treated with a
distributed systems mindset, not a code execution one.

> Of course, D is still in it's infancy but it would be cool it 
> someone was interested in trying to make a D for java and see 
> where it goes. I think something useful would come out of it. 
> (Please don't say I should do it either...)

D is not in it's infancy, it is 10 years old and in language terms
should be mature and entering mainstream use. Java and C are weird
special cases, but C++, Groovy, Python, JRuby, most other languages take
5 years to develop, 5 years to settle and if they are not major players
by then will disappear. Of course most language don't get that far.

D is superior to C++ in almost every way except that it has no traction.

I am thinking that C++ is no longer the thing that D is able to compete
with, just let that community be. C is also shrinking as people realize
it is a niche language for operating systems and runtime systems. The
action is native vs. JVM vs. PVM.

The native+PVM has massive traction in computational arenas. JVM remains
the major player other than .NET in almost all Internet life. Go is
having a good go (!) at challenging this on behalf of native.

Marketingwise D is at a crossroads: continue to see itself as a C++
beater, or a native language for the Internet world. This is about
mindset and attitude of people here in this mailing list and the way
they present D to the world.

vibe.d could be the making of D if pushed appropriately. But it needs a
client as well as server activity. GtkD, QtD, wxD, OSXD, WindowsD, i.e.
connection into the standard graphics systems, are needed. SQLD,
MongoDBD, NeoD, are needed. The effort should be on embedding D in a
flexible context.

Go has motored a long way down this road already and is beginning to get
mind share as the native code system for the Internet. It has a huge
distance to travel to challenge Java and ASP.NET, but it is way ahead of
D.
 
-- 
Russel.
=============================================================================
Dr Russel Winder      t: +44 20 7585 2200   voip: sip:russel.winder@ekiga.net
41 Buckmaster Road    m: +44 7770 465 077   xmpp: russel@winder.org.uk
London SW11 1EN, UK   w: www.russel.org.uk  skype: russel_winder
February 19, 2013
Re: Java binaries
Am 17.02.2013 21:47, schrieb Walter Bright:
> On 2/17/2013 1:46 AM, Russel Winder wrote:
>> The world is split into native code, PVM, JVM, JavaScript/ECMAScript. D
>> only really has a play in one of these, and needs to get real traction
>> there first before looking for new lands to conquer. Else it risks being
>> seen as a solution looking for a problem to solve.
>
> I agree. There was at one time a D implementation on .net, but it
> suffered from .net's lack of support for pointers, which meant that
> slices performed poorly.
>

So how are C++ and C# pointers done in IL ?
February 19, 2013
Re: Java binaries
On Tuesday, 19 February 2013 at 21:30:53 UTC, Paulo Pinto wrote:
> Am 17.02.2013 21:47, schrieb Walter Bright:
>> On 2/17/2013 1:46 AM, Russel Winder wrote:
>>> The world is split into native code, PVM, JVM, 
>>> JavaScript/ECMAScript. D
>>> only really has a play in one of these, and needs to get real 
>>> traction
>>> there first before looking for new lands to conquer. Else it 
>>> risks being
>>> seen as a solution looking for a problem to solve.
>>
>> I agree. There was at one time a D implementation on .net, but 
>> it
>> suffered from .net's lack of support for pointers, which meant 
>> that
>> slices performed poorly.
>>
>
> So how are C++ and C# pointers done in IL ?

There are two kind of pointers in C#: managed and unmanaged. 
Wrapped in a fixed statement (just to tell the garbage collector 
to keep fixed references), C# pointers will behave like any 
native language pointer. This is not the first topic where I read 
that misconception that slices are a problem for IL. From .net 
2.0 (9 years ago) there is the ArraySegment<T> type doing exactly 
what D slices do. Also, in C# arrays are implicitely convertible 
to pointers.

Anyway, I don't see any use for a D IL compiler, since probably 
the language syntax will look 90% like C#.
« First   ‹ Prev
1 2
Top | Discussion index | About this forum | D home