• Ryan Voots (5/5) Sep 10 2014 An article today about the garbage collector and the ensuing
• Joakim (2/7) Sep 10 2014 Orvid, where's that new GC when we need it? ;)
• Peter Alexander (10/11) Sep 10 2014 Andrei posted this in the reddit thread:
• Andrei Alexandrescu (2/11) Sep 10 2014 It was about time! -- Andrei
• deadalnix (4/5) Sep 10 2014 Tychus, is that you ?
• Kagamin (2/5) Sep 11 2014 Is it true about pointers? Which functions?
• Marco Leise (12/18) Sep 11 2014 Immutable data structures cannot have pointers changed or set
• Kagamin (3/11) Sep 13 2014 Can get in a way, when you need a thread-local immutable object.
• "Marc =?UTF-8?B?U2Now7x0eiI=?= <schuetzm gmx.net> (3/15) Sep 13 2014 Hmm... when is that necessary? Wouldn't `const` be enough?
• Timon Gehr (4/6) Sep 13 2014 const prevents modification, but does not guarantee that no modification...
• "Marc =?UTF-8?B?U2Now7x0eiI=?= <schuetzm gmx.net> (13/21) Sep 14 2014 But as it is thread-local, is it really relevant (for
• Kagamin (1/1) Sep 13 2014 And strong purity.
• Kagamin (14/17) Sep 13 2014 Also a certain discipline is required to construct
• Chris (16/36) Sep 11 2014 Thank you very much for tackling this problem.
• ketmar via Digitalmars-d (3/4) Sep 11 2014 she has. ;-)
• Chris (11/15) Sep 11 2014 Japers, I wasn't sure, if it was he or she and just gambled on a
• Rikki Cattermole (5/20) Sep 11 2014 *starts drooling at the idea of using Jade for Cmsed*
• Chris (50/81) Sep 11 2014 Of course. Once I have a "clean" version. The first test version
• Rikki Cattermole (7/78) Sep 11 2014 I see hmm, I may compile a custom lua dll then with lanes (think
• Chris (6/11) Sep 11 2014 Maybe I can set up a simple test version for you, when I find the
• Chris (5/5) Sep 12 2014 On Thursday, 11 September 2014 at 11:28:38 UTC, Rikki Cattermole
• Rikki Cattermole (3/7) Sep 12 2014 Okay sweet.
• Chris (3/14) Sep 12 2014 Ok, I've sent it.
• Bastiaan Veelo (1/1) Sep 11 2014 Yay!

"Ryan Voots" <simcop2387 simcop2387.info> writes:

An article today about the garbage collector and the ensuing 
discussion from it

http://pointersgonewild.wordpress.com/2014/09/09/ds-garbage-collector-problem/

https://news.ycombinator.com/item?id=8297091

http://www.reddit.com/r/programming/comments/2g03af/ds_garbage_collector_problem/

"Joakim" <dlang joakim.airpost.net> writes:

On Wednesday, 10 September 2014 at 18:58:58 UTC, Ryan Voots wrote:
 An article today about the garbage collector and the ensuing 
 discussion from it

 http://pointersgonewild.wordpress.com/2014/09/09/ds-garbage-collector-problem/

 https://news.ycombinator.com/item?id=8297091

 http://www.reddit.com/r/programming/comments/2g03af/ds_garbage_collector_problem/

Orvid, where's that new GC when we need it? ;)

"Peter Alexander" <peter.alexander.au gmail.com> writes:

On Wednesday, 10 September 2014 at 20:01:40 UTC, Joakim wrote:
 Orvid, where's that new GC when we need it? ;)

Andrei posted this in the reddit thread:

"OK that does it. I'm going to redesign and implement D's tracing 
garbage collector using the core allocator I wrote a short while 
ago.

Fatefully Walter Bright and I were talking about the GC over 
dinner last night (I'm at cppcon in Seattle!) and I figured if 
this is what matters for D, I'll have to do it. And it does 
matter. It's actually not that difficult especially given that we 
have a solid allocator backend."

Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:

On 9/10/14, 1:11 PM, Peter Alexander wrote:
 On Wednesday, 10 September 2014 at 20:01:40 UTC, Joakim wrote:
 Orvid, where's that new GC when we need it? ;)

 Andrei posted this in the reddit thread:

 "OK that does it. I'm going to redesign and implement D's tracing
 garbage collector using the core allocator I wrote a short while ago.

 Fatefully Walter Bright and I were talking about the GC over dinner last
 night (I'm at cppcon in Seattle!) and I figured if this is what matters
 for D, I'll have to do it. And it does matter. It's actually not that
 difficult especially given that we have a solid allocator backend."

It was about time! -- Andrei

"deadalnix" <deadalnix gmail.com> writes:

On Thursday, 11 September 2014 at 00:27:40 UTC, Andrei
Alexandrescu wrote:
 It was about time! -- Andrei

Tychus, is that you ?

http://www.blizzcon2013.com/wp-content/uploads/2012/09/starcraft_ii_beta_time.jpg

"Kagamin" <spam here.lot> writes:

There are various api the compiler use to allocate from the GC. 
Some do not specify if the allocated memory contains pointers or 
not, and none do specify the type qualifier of the memory.

Is it true about pointers? Which functions?
And why type qualifiers matter?

Marco Leise <Marco.Leise gmx.de> writes:

Am Thu, 11 Sep 2014 14:30:05 +0000
schrieb "Kagamin" <spam here.lot>:

There are various api the compiler use to allocate from the GC. 
Some do not specify if the allocated memory contains pointers or 
not, and none do specify the type qualifier of the memory.

 
 Is it true about pointers? Which functions?
 And why type qualifiers matter?

Immutable data structures cannot have pointers changed or set
to null. Also they can only reference other immutable data.
This means that they form sort of a big blob that is kept
alive by one or more pointers to it, but the GC never needs
to check the immutable pointers inside of it.

Shared/unshared may affect implementations that provide thread
local GC. E.g. only shared data needs to be handled by a
global stop the world GC. I'm not sure though.

-- 
Marco

"Kagamin" <spam here.lot> writes:

On Thursday, 11 September 2014 at 16:26:37 UTC, Marco Leise wrote:
 Immutable data structures cannot have pointers changed or set
 to null. Also they can only reference other immutable data.
 This means that they form sort of a big blob that is kept
 alive by one or more pointers to it, but the GC never needs
 to check the immutable pointers inside of it.

GC still should free unreachable parts of that blob.

 Shared/unshared may affect implementations that provide thread
 local GC. E.g. only shared data needs to be handled by a
 global stop the world GC. I'm not sure though.

Can get in a way, when you need a thread-local immutable object.

"Marc =?UTF-8?B?U2Now7x0eiI=?= <schuetzm gmx.net> writes:

On Saturday, 13 September 2014 at 18:06:47 UTC, Kagamin wrote:
 On Thursday, 11 September 2014 at 16:26:37 UTC, Marco Leise 
 wrote:
 Immutable data structures cannot have pointers changed or set
 to null. Also they can only reference other immutable data.
 This means that they form sort of a big blob that is kept
 alive by one or more pointers to it, but the GC never needs
 to check the immutable pointers inside of it.

 GC still should free unreachable parts of that blob.

 Shared/unshared may affect implementations that provide thread
 local GC. E.g. only shared data needs to be handled by a
 global stop the world GC. I'm not sure though.

 Can get in a way, when you need a thread-local immutable object.

Hmm... when is that necessary? Wouldn't `const` be enough? 
AFAICS, `immutable` is mostly useful for shared data.

Timon Gehr <timon.gehr gmx.ch> writes:

On 09/13/2014 09:07 PM, "Marc =?UTF-8?B?U2Now7x0eiI=?= 
<schuetzm gmx.net>" wrote:
 Wouldn't `const` be enough? AFAICS, `immutable` is mostly useful for
 shared data.

const prevents modification, but does not guarantee that no modification 
takes place elsewhere. I.e. it enables fewer program transformations.

"Marc =?UTF-8?B?U2Now7x0eiI=?= <schuetzm gmx.net> writes:

On Saturday, 13 September 2014 at 19:20:51 UTC, Timon Gehr wrote:
 On 09/13/2014 09:07 PM, "Marc =?UTF-8?B?U2Now7x0eiI=?= 
 <schuetzm gmx.net>" wrote:
 Wouldn't `const` be enough? AFAICS, `immutable` is mostly 
 useful for
 shared data.

 const prevents modification, but does not guarantee that no 
 modification takes place elsewhere. I.e. it enables fewer 
 program transformations.

But as it is thread-local, is it really relevant (for 
optimization)? I can see two situations where it can potentially 
matter: pointer parameter aliasing, and calls to 
function/delegate calls that might modify a value referenced by a 
pointer.

In practice the latter is probably not so important for 
optimizations, because the compiler would most likely have a hard 
time caching a value across a function call because of register 
pressure, so a reload would be necessary anyway. I don't know 
about parameter aliasing, but I guess it only makes a difference 
in corner cases. In these cases, it's easy to forbid it by 
contract (as slice copying does).

"Kagamin" <spam here.lot> writes:

And strong purity.

"Kagamin" <spam here.lot> writes:

On Thursday, 11 September 2014 at 16:26:37 UTC, Marco Leise wrote:
 Shared/unshared may affect implementations that provide thread
 local GC. E.g. only shared data needs to be handled by a
 global stop the world GC. I'm not sure though.

Also a certain discipline is required to construct 
shared/immutable object from the start instead of casting from 
thread-local mutable. And then how to add an object to a shared 
collection?

//callable without lock
void add(shared Object) shared;
//allocated thread-local object
void add(Object);
//but unshared collection contains unshared objects
void add(shared Object);
//thread-local object again
void add(Object) shared;

?

"Chris" <wendlec tcd.ie> writes:

On Thursday, 11 September 2014 at 00:27:40 UTC, Andrei 
Alexandrescu wrote:
 On 9/10/14, 1:11 PM, Peter Alexander wrote:
 On Wednesday, 10 September 2014 at 20:01:40 UTC, Joakim wrote:
 Orvid, where's that new GC when we need it? ;)

 Andrei posted this in the reddit thread:

 "OK that does it. I'm going to redesign and implement D's 
 tracing
 garbage collector using the core allocator I wrote a short 
 while ago.

 Fatefully Walter Bright and I were talking about the GC over 
 dinner last
 night (I'm at cppcon in Seattle!) and I figured if this is 
 what matters
 for D, I'll have to do it. And it does matter. It's actually 
 not that
 difficult especially given that we have a solid allocator 
 backend."

 It was about time! -- Andrei

Thank you very much for tackling this problem.

GC hasn't been a problem for me (yet!), but the article is very 
convincing. Writing an JIT compiler whose performance is as good 
as or even better than C(++)'s is something one should be able to 
do in D, there's no doubt about it.

The author of the aforementioned article apologizes for the "bad 
publicity" he may have caused. On the contrary, I think he has 
done D a big favor. Through the attention his article got, the 
(programming) world knows now that D will get a much better GC, 
which will (hopefully) bring D back on the radar of those who had 
already discarded it because of its poor GC. Also, unlike the 
corporate world, we should not be afraid of "bad publicity". If 
there is a real problem, it's better to talk about it and fix it 
than to cover it up and drag it along.

ketmar via Digitalmars-d <digitalmars-d puremagic.com> writes:

On Thu, 11 Sep 2014 09:29:41 +0000
Chris via Digitalmars-d <digitalmars-d puremagic.com> wrote:

 he has

she has. ;-)

"Chris" <wendlec tcd.ie> writes:

On Thursday, 11 September 2014 at 09:37:04 UTC, ketmar via 
Digitalmars-d wrote:
 On Thu, 11 Sep 2014 09:29:41 +0000
 Chris via Digitalmars-d <digitalmars-d puremagic.com> wrote:

 he has

 she has. ;-)

Japers, I wasn't sure, if it was he or she and just gambled on a 
50% chance :) My apologies.

PS and OT I hope Higgs will become a long term project. Imagine, 
you could combine Higgs and vibe.d. You could write your own D 
extensions for server side JS. In this way you could have 
projects where anyone who knows JS could contribute (good bye 
PHP), no need to know D. I have a test version of a LuaD + Lua 
Server Pages + vibe.d server. Works very well. JS is even more 
wide spread than Lua (albeit inferior as a language).

Rikki Cattermole <alphaglosined gmail.com> writes:

On 11/09/2014 10:05 p.m., Chris wrote:
 On Thursday, 11 September 2014 at 09:37:04 UTC, ketmar via Digitalmars-d
 wrote:
 On Thu, 11 Sep 2014 09:29:41 +0000
 Chris via Digitalmars-d <digitalmars-d puremagic.com> wrote:

 he has

 she has. ;-)

 Japers, I wasn't sure, if it was he or she and just gambled on a 50%
 chance :) My apologies.

 PS and OT I hope Higgs will become a long term project. Imagine, you
 could combine Higgs and vibe.d. You could write your own D extensions
 for server side JS. In this way you could have projects where anyone who
 knows JS could contribute (good bye PHP), no need to know D. I have a
 test version of a LuaD + Lua Server Pages + vibe.d server. Works very
 well. JS is even more wide spread than Lua (albeit inferior as a language).

*starts drooling at the idea of using Jade for Cmsed*
Would seriously fix so many problems with templates.

Any chance I could get a copy of your test for LuaD + Lua Server Pages?
I may want to investigate that angle as well.

"Chris" <wendlec tcd.ie> writes:

On Thursday, 11 September 2014 at 10:23:56 UTC, Rikki Cattermole 
wrote:
 On 11/09/2014 10:05 p.m., Chris wrote:
 On Thursday, 11 September 2014 at 09:37:04 UTC, ketmar via 
 Digitalmars-d
 wrote:
 On Thu, 11 Sep 2014 09:29:41 +0000
 Chris via Digitalmars-d <digitalmars-d puremagic.com> wrote:

 he has

 she has. ;-)

 Japers, I wasn't sure, if it was he or she and just gambled on 
 a 50%
 chance :) My apologies.

 PS and OT I hope Higgs will become a long term project. 
 Imagine, you
 could combine Higgs and vibe.d. You could write your own D 
 extensions
 for server side JS. In this way you could have projects where 
 anyone who
 knows JS could contribute (good bye PHP), no need to know D. I 
 have a
 test version of a LuaD + Lua Server Pages + vibe.d server. 
 Works very
 well. JS is even more wide spread than Lua (albeit inferior as 
 a language).

 *starts drooling at the idea of using Jade for Cmsed*
 Would seriously fix so many problems with templates.

 Any chance I could get a copy of your test for LuaD + Lua 
 Server Pages?
 I may want to investigate that angle as well.

Of course. Once I have a "clean" version. The first test version 
is full of embarrassing hit-and-miss code, commented blocks etc.

But you could probably glue one together yourself.

1. get Open Luasp http://www.luasp.org/
2. get LuaD
3. create a vibe.d project (a normal default project will do, for 
testing at least)
4. link your project to libluad and liblualsp (or lualsp.so)

In you vibe.d code route to your lua handling function

shared static this() {
   [...]
   router.any("*", &luaTest);
   [...]
}

void luaTest(HTTPServerRequest req, HTTPServerResponse res) {
   // do your lualsp / LuaD thing
}

Then you have basically a few options. Use Lua code as in

test.lua:

repuire("lualsp")
dofile_lsp("example.html")

in (Lua)D:

lua.doFile("test.lua")

or

lua.doString("require('lualsp')");
lua.doString("dofile_lsp('public/example1.html')");

or (what I do), call the functions provided by lualsp directly

extern (C) int luaopen_lualsp(lua_State *L);
extern (C) int luaL_do_lsp_file(lua_State* L,const char* 
filename);
[etc....]

Or a combination of the above.

Just have a look at the various methods provided by both LuaD and 
lualsp.

Note: lualsp writes to stdout, make sure you use

std.c.stdio.stdout

to grab the output. Not the one provided in Phobos' std.stdio

Excerpt from dub.json

"libs": [
     "luad",
     "lua5.1",
     "lualsp"
	],

Make sure you use Lua 5.1. LuaD (afsaik) only supports 5.1 as of 
now.

It works like PHP (echo, print etc). I put this together in order 
to avoid PHP in the future. Lua is a sound language and you can 
expect developers to be familiar with it.

Rikki Cattermole <alphaglosined gmail.com> writes:

On 11/09/2014 11:13 p.m., Chris wrote:
 On Thursday, 11 September 2014 at 10:23:56 UTC, Rikki Cattermole wrote:
 On 11/09/2014 10:05 p.m., Chris wrote:
 On Thursday, 11 September 2014 at 09:37:04 UTC, ketmar via Digitalmars-d
 wrote:
 On Thu, 11 Sep 2014 09:29:41 +0000
 Chris via Digitalmars-d <digitalmars-d puremagic.com> wrote:

 he has

 she has. ;-)

 Japers, I wasn't sure, if it was he or she and just gambled on a 50%
 chance :) My apologies.

 PS and OT I hope Higgs will become a long term project. Imagine, you
 could combine Higgs and vibe.d. You could write your own D extensions
 for server side JS. In this way you could have projects where anyone who
 knows JS could contribute (good bye PHP), no need to know D. I have a
 test version of a LuaD + Lua Server Pages + vibe.d server. Works very
 well. JS is even more wide spread than Lua (albeit inferior as a
 language).

 *starts drooling at the idea of using Jade for Cmsed*
 Would seriously fix so many problems with templates.

 Any chance I could get a copy of your test for LuaD + Lua Server Pages?
 I may want to investigate that angle as well.

 Of course. Once I have a "clean" version. The first test version is full
 of embarrassing hit-and-miss code, commented blocks etc.

Personally I'm not worried. I wouldn't be able to use it in any form.

 But you could probably glue one together yourself.

 1. get Open Luasp http://www.luasp.org/
 2. get LuaD
 3. create a vibe.d project (a normal default project will do, for
 testing at least)
 4. link your project to libluad and liblualsp (or lualsp.so)

 In you vibe.d code route to your lua handling function

 shared static this() {
    [...]
    router.any("*", &luaTest);
    [...]
 }

 void luaTest(HTTPServerRequest req, HTTPServerResponse res) {
    // do your lualsp / LuaD thing
 }

 Then you have basically a few options. Use Lua code as in

 test.lua:

 repuire("lualsp")
 dofile_lsp("example.html")

 in (Lua)D:

 lua.doFile("test.lua")

 or

 lua.doString("require('lualsp')");
 lua.doString("dofile_lsp('public/example1.html')");

 or (what I do), call the functions provided by lualsp directly

 extern (C) int luaopen_lualsp(lua_State *L);
 extern (C) int luaL_do_lsp_file(lua_State* L,const char* filename);
 [etc....]

 Or a combination of the above.

 Just have a look at the various methods provided by both LuaD and lualsp.

 Note: lualsp writes to stdout, make sure you use

 std.c.stdio.stdout

 to grab the output. Not the one provided in Phobos' std.stdio

 Excerpt from dub.json

 "libs": [
      "luad",
      "lua5.1",
      "lualsp"
      ],

 Make sure you use Lua 5.1. LuaD (afsaik) only supports 5.1 as of now.

 It works like PHP (echo, print etc). I put this together in order to
 avoid PHP in the future. Lua is a sound language and you can expect
 developers to be familiar with it.


I see hmm, I may compile a custom lua dll then with lanes (think 
threading). Well maybe, we shall see.
Might also be a good idea to hook it up to my skeleton tool[0] to enable 
using e.g. gists for require's.

[0] https://github.com/rikkimax/skeleton

"Chris" <wendlec tcd.ie> writes:

On Thursday, 11 September 2014 at 11:28:38 UTC, Rikki Cattermole 
wrote:
 I see hmm, I may compile a custom lua dll then with lanes 
 (think threading). Well maybe, we shall see.
 Might also be a good idea to hook it up to my skeleton tool[0] 
 to enable using e.g. gists for require's.

 [0] https://github.com/rikkimax/skeleton

Maybe I can set up a simple test version for you, when I find the 
time. Can't promise but I'll try. One thing I haven't looked into 
yet is a clever way of handling the output in stdout. At the 
moment, I write to a temporary file ("test.txt") I read in again.

"Chris" <wendlec tcd.ie> writes:

On Thursday, 11 September 2014 at 11:28:38 UTC, Rikki Cattermole 
wrote:

Rikki, I have a basic LuaD / vibe.d / Lua LSP server now. I 
needed actually less code than expected. If you give me your 
email address, I can send it to you. It has a simple form example.

Rikki Cattermole <alphaglosined gmail.com> writes:

On 12/09/2014 11:30 p.m., Chris wrote:
 On Thursday, 11 September 2014 at 11:28:38 UTC, Rikki Cattermole wrote:

 Rikki, I have a basic LuaD / vibe.d / Lua LSP server now. I needed
 actually less code than expected. If you give me your email address, I
 can send it to you. It has a simple form example.

Okay sweet.
alphaglosined /at/ gmail /dot/ com

"Chris" <wendlec tcd.ie> writes:

On Friday, 12 September 2014 at 11:46:08 UTC, Rikki Cattermole 
wrote:
 On 12/09/2014 11:30 p.m., Chris wrote:
 On Thursday, 11 September 2014 at 11:28:38 UTC, Rikki 
 Cattermole wrote:

 Rikki, I have a basic LuaD / vibe.d / Lua LSP server now. I 
 needed
 actually less code than expected. If you give me your email 
 address, I
 can send it to you. It has a simple form example.

 Okay sweet.
 alphaglosined /at/ gmail /dot/ com

Ok, I've sent it.

"Bastiaan Veelo" <Bastiaan Veelo.net> writes:

Yay!