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digitalmars.D - Webassembly?

reply Wulfklaue <wulfklaue wulfklaue.com> writes:
Is there a future where we can see WebAssembly as part of D? 
Seeing Rusts backbone already producing wasm is impressive.

WebAssembly currently does not support a GC ...so it fair the 
assume that this will be the main issue for LDC?

I see the move towards one language for back and front-end as the 
future.
Jul 06 2017
next sibling parent reply bauss <jj_1337 live.dk> writes:
On Thursday, 6 July 2017 at 15:34:08 UTC, Wulfklaue wrote:

 Is there a future where we can see WebAssembly as part of D? 
 Seeing Rusts backbone already producing wasm is impressive.

 WebAssembly currently does not support a GC ...so it fair the 
 assume that this will be the main issue for LDC?

 I see the move towards one language for back and front-end as 
 the future.


I'm just curious how it doesn't support GC? Like if you can 
allocate and free memory then you can have a GC.
Jul 06 2017
next sibling parent Wulfklaue <wulfklaue wulfklaue.com> writes:
On Thursday, 6 July 2017 at 17:19:34 UTC, bauss wrote:

 I'm just curious how it doesn't support GC? Like if you can 
 allocate and free memory then you can have a GC.


Currently there is no native GC build into WebAssembly. This is 
planned for the future.

If your language is designed around allocating and freeing memory 
manually, you have no issue with WebAssembly. C/C++/Rust ...

But you can not program in D fashion ( where the GC takes care of 
things ). It means you need to write the allocation and freeing 
all the time for any code that targets WebAssembly. hat also 
means no std library etc ... Think of it as writing pure  nogc 
code ( what currently breaks like half the standard library ).

WebAssembly has plans for a native GC build into the design for 
the next version so that languages that have there own GC, can 
target this and not run into the issue of manually allocating and 


The other option is for the language to have there own GC 
included that targets WebAssembly into the compiled wasm file but 
that adds overhead. And is more work for the language to support. 
That is why a lot of languages that have GCs are on the fence and 
are waiting for the default GC.

GC are nice and well but at times having a pure no-gc language 
does have its advantages ;)
Jul 06 2017
prev sibling parent reply Joakim <dlang joakim.fea.st> writes:
On Thursday, 6 July 2017 at 17:19:34 UTC, bauss wrote:

 On Thursday, 6 July 2017 at 15:34:08 UTC, Wulfklaue wrote:

 Is there a future where we can see WebAssembly as part of D? 
 Seeing Rusts backbone already producing wasm is impressive.

 WebAssembly currently does not support a GC ...so it fair the 
 assume that this will be the main issue for LDC?

 I see the move towards one language for back and front-end as 
 the future.


 I'm just curious how it doesn't support GC? Like if you can 
 allocate and free memory then you can have a GC.


People usually point to this design doc:

https://github.com/WebAssembly/design/blob/master/GC.md

I don't know much about GC or their IR, but I get the impression 
it's more about integrating with the browser's GC, so you can 
seamlessly pass objects to javascript.  I believe people have 
written their own GCs that target webasm, so the D GC can likely 
be made to do the same.
Jul 06 2017
next sibling parent kinke <noone nowhere.com> writes:
On Thursday, 6 July 2017 at 18:26:18 UTC, Joakim wrote:

 On Thursday, 6 July 2017 at 17:19:34 UTC, bauss wrote:

 On Thursday, 6 July 2017 at 15:34:08 UTC, Wulfklaue wrote:

 Is there a future where we can see WebAssembly as part of D? 
 Seeing Rusts backbone already producing wasm is impressive.

 WebAssembly currently does not support a GC ...so it fair the 
 assume that this will be the main issue for LDC?

 I see the move towards one language for back and front-end as 
 the future.


 I'm just curious how it doesn't support GC? Like if you can 
 allocate and free memory then you can have a GC.


 People usually point to this design doc:

 https://github.com/WebAssembly/design/blob/master/GC.md

 I don't know much about GC or their IR, but I get the 
 impression it's more about integrating with the browser's GC, 
 so you can seamlessly pass objects to javascript.  I believe 
 people have written their own GCs that target webasm, so the D 
 GC can likely be made to do the same.


Wow, quite an opportunity for D I'd say. A D frontend able to 
interop with the myriads of existing Javascript libraries, using 
the browser's GC and its DOM as GUI toolkit. Coupled with a 
vibe.d backend. Frontend and backend sharing D files describing 
their common interface.
Jul 06 2017
prev sibling parent reply Ola Fosheim Grostad <ola.fosheim.grostad gmail.com> writes:
On Thursday, 6 July 2017 at 18:26:18 UTC, Joakim wrote:

 so you can seamlessly pass objects to javascript.  I believe 
 people have written their own GCs that target webasm, so the D 
 GC can likely be made to do the same.


You would have to emulate the stack...
Jul 06 2017
parent Jakob Bornecrantz <wallbraker gmail.com> writes:
On Thursday, 6 July 2017 at 22:58:36 UTC, Ola Fosheim Grostad 
wrote:

 On Thursday, 6 July 2017 at 18:26:18 UTC, Joakim wrote:

 so you can seamlessly pass objects to javascript.  I believe 
 people have written their own GCs that target webasm, so the D 
 GC can likely be made to do the same.


 You would have to emulate the stack...


WebAssembly has linear memory that you can scan just like normal 
memory. C programs use it for those values on the stack that it 
needs a pointer to. For other values they are put on the safe 
stack, you can only read the value not the memory backing it.

So there is a problem of pointers going on the safe stack so you 
need to make sure to not optimise those pointers to the safe 
stack.

But in short, the D GC will work just fine, just need to be a bit 
carefull with pointers on the stack.

Cheers, Jakob.
Jul 06 2017
prev sibling parent Wulfklaue <wulfklaue wulfklaue.com> writes:
Here is some nice stuff:

https://youtu.be/MiLAE6HMr10?t=32m5s



Funny thing being, that it compiles down to a 250k download, what 
is actually much less then some of the angular 1/2/4 code that we 
have at work.

And people at work wonder why i am a strong advocate for 
WebAssembly... O_o
Jul 11 2017