www.digitalmars.com         C & C++   DMDScript  

digitalmars.D - Java binaries

reply "js.mdnq" <js_adddot+mdng gmail.com> writes:
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).
Feb 16 2013
next sibling parent reply Walter Bright <newshound2 digitalmars.com> writes:
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.
Feb 16 2013
parent reply "js.mdnq" <js_adddot+mdng gmail.com> writes:
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.
Feb 17 2013
parent reply Russel Winder <russel winder.org.uk> writes:
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=20
 to take advantage
 of what java offers. (e.g., the ability to run d code inside a=20
 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=20
 functionality(obviously stuff
 like asm isn't going to work) but basically the ability to use=20
 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=20
 problems.


=20
 Java does have pointers... you just can't get to them easily. At=20
 the very least, you could allocate and manage your own chunk of=20
 memory and do all the pointer arithmetic yourself on that chunk.=20
 This would require the chunk to be pinned in some way and the GC=20
 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=20
 manager for each platform and all pointer arithmetic is passed=20
 through that. Of course, if one goes this far then any "javaD"=20
 would need to be able to work well with importing java libraries=20
 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.

--=20
Russel.
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D
Dr Russel Winder      t: +44 20 7585 2200   voip: sip:russel.winder ekiga.n=
et
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
Feb 17 2013
next sibling parent reply Walter Bright <newshound2 digitalmars.com> writes:
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.
Feb 17 2013
parent reply Paulo Pinto <pjmlp progtools.org> writes:
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.
Feb 19 2013
parent reply "rumbu" <rumbu rumbu.ro> writes:
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.






Wrapped in a fixed statement (just to tell the garbage collector 

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 

to pointers.

Anyway, I don't see any use for a D IL compiler, since probably
Feb 19 2013
next sibling parent Paulo Pinto <pjmlp progtools.org> writes:
Am 19.02.2013 22:59, schrieb rumbu:

 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.






 a fixed statement (just to tell the garbage collector to keep fixed

 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

 are implicitely convertible to pointers.
 ...


I know .NET since the early pre-Beta days as my employer at the time, 
had the privilege to be one of the few Microsoft Partners in Portugal 
with access to the technology.


C++, later superseded by C++/CLI. Hence my question. :)

--
Paulo
Feb 19 2013
prev sibling next sibling parent Timon Gehr <timon.gehr gmx.ch> writes:
On 02/19/2013 10:59 PM, rumbu wrote:

 ...

 Anyway, I don't see any use for a D IL compiler, since probably the



Even if that was true, so what?
Feb 19 2013
prev sibling parent reply "David Piepgrass" <qwertie256 gmail.com> writes:




 Wrapped in a fixed statement (just to tell the garbage 

 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> 

 implicitely convertible to pointers.


IIRC, the biggest incompatibility between D and .NET is that D 
pointers can point to the stack, to unmanaged (non-GC) memory or 
to managed (GC) memory, while simultaneously having unlimited 
lifetime. In .NET, arguments that are passed by reference can 
point to GC or non-GC memory, but pointers inside objects 
(classes or boxed structs) can only point to (1) non-GC non-stack 
memory OR (2) the beginning of a GC object. The key problem: a 
single pointer cannot be used for both purposes!

D pointers and ranges can point to stack, GC or non-GC memory, 
regardless of the location of the pointer or range itself. Also, 
D pointers can point to the interior of an object and not just 
the beginning, while .NET pointers, in general, cannot.

This doesn't make a D implementation for .NET impossible, but if 
you want to run arbitrary D code on .NET, I think it would have 
to run inefficiently because it would constantly have to work 
around limitations of .NET. I think doing D in .NET efficiently 
would require a specialized version of D, or something.

Note that plain old C++ can be used in .NET because C++ pointers 
can't point to GC memory without special .NET-specific types. 
Thus, old-fashioned C++ avoids problems related to the .NET 
garbage collector.


 Anyway, I don't see any use for a D IL compiler, since probably 





whole.
Feb 19 2013
parent reply "rumbu" <rumbu rumbu.ro> writes:
On Wednesday, 20 February 2013 at 00:15:00 UTC, David Piepgrass 
wrote:




 the whole.



with the current language semantics. But, once D will be adapted 
to generate IL code, most of advantages will be lost. You cannot 
have assembler code (may be IL code, but this can be achieved 

redundant because of the intrinsic runtime reflection, most of 
the templates will be constrained to generic types. In a 

framework. Also because of lack of some D features (like 
readonly, mutiple interface implementation of the same method, 
namespaces), more keywords will be needed to describe the code 


The irony is the fact that digging in the forum history, you will 

the recent changes, "alias" has evolved to the exact syntax of 


If the initial audience of D was the C++ programmer, I think it's 

programmer since the syntax is very similar. The most important 


programmer is out of his interest, imho.
Feb 20 2013
parent "Paulo Pinto" <pjmlp progtools.org> writes:
On Wednesday, 20 February 2013 at 08:38:00 UTC, rumbu wrote:

 On Wednesday, 20 February 2013 at 00:15:00 UTC, David Piepgrass 
 wrote:




 the whole.




 adapted to generate IL code, most of advantages will be lost. 
 You cannot have assembler code (may be IL code, but this can be 

 become redundant because of the intrinsic runtime reflection, 
 most of the templates will be constrained to generic types. In 

 .net framework. Also because of lack of some D features (like 
 readonly, mutiple interface implementation of the same method, 
 namespaces), more keywords will be needed to describe the code 


 The irony is the fact that digging in the forum history, you 

 look at the recent changes, "alias" has evolved to the exact 


 If the initial audience of D was the C++ programmer, I think 

 programmer since the syntax is very similar. The most important 


 programmer is out of his interest, imho.


A problem here is that Microsoft is probably in the process of 
also offering standalone compilation for .NET languages as well.

Windows Phone 8 .NET applications get compiled to native code, 
they are not JITted.

They might as well decide to use the same solution instead of 
NGEN on the desktop.

--
Paulo
Feb 20 2013
prev sibling parent reply "js.mdnq" <js_adddot+mdng gmail.com> writes:
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...)
Feb 17 2013
parent Russel Winder <russel winder.org.uk> writes:
On Mon, 2013-02-18 at 03:37 +0100, js.mdnq wrote:
[=E2=80=A6]

 Everything started out as minor and if D's language features are=20
 truly good and D is as well designed as some think then people=20
 will migrate to it. Essentially "If you build it they will come"=20
 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=20
 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=20
 do not need another one. Hence, it would be nice to leverage=20
 java, which already has build up it's user base to further the D=20
 language paradigm. I like D but so far it doesn't seem to be=20
 going anywhere. Why? Because one already has all these other=20
 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:
=20
 Suppose with a snap of your fingers you could have the following=20
 products:
=20
 High stable and performant D compiler for all the major=20
 platforms(including many embedded) with a large collection of=20
 support tools.
=20
 A D virtual machine that runs on many platforms. A D for java=20
 compiler that compiles almost any D program into java bytecode=20
 and use java libraries.
=20
 etc...
=20
 Now, if you had all this stuff magically out there do you think=20
 that the userbase for D would explode? I do... In fact, it would=20
 happen for most decent languages. (of course, we could argue=20
 about the exact details but D would become a major player within=20
 a few years)
=20
 Hence, having this stuff is important for D's success. Of course,=20
 it may not be possible in some cases or sacrifices have to be=20
 made. In any case I'm not convinced that a D for java can't be=20
 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=20
 someone was interested in trying to make a D for java and see=20
 where it goes. I think something useful would come out of it.=20
 (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.
 =20
--=20
Russel.
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D
Dr Russel Winder      t: +44 20 7585 2200   voip: sip:russel.winder ekiga.n=
et
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
Feb 17 2013
prev sibling parent "Tove" <tove fransson.se> writes:
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/
Feb 17 2013