Re: WASM / Web Assembly ecl in a browser

Hi all,

Thanks for this thread, I've been very interested in getting my common 
lisp project to run in ECL and Emscripten.  A little before the release, 
I managed to hack my way through the instructions to get an ECL 
Emscripten build working with the dialog prompted ECL terminal.  I'd 
like to try and work out how to put together the following 2 proof of 
concepts as a springboard for future work.

1. Figuring out how to just bundle my entire ASDF project with enough of 
it's dependencies, so that I can instantiate something (like a class or 
a struct) from my project in the REPL.
2. Figure out how to get an OpenGL triangle working using cl-opengl 
along with the glfw or sdl2 support built into Emscripten.

I'm more or less totally new to Emscripten, and I'm in the process of 
getting my source to run on ECL (it at least fully loads now and can run 
the unit tests with a few passing. It currently has dependencies on 
Lispworks, but i'm making fair progress with it getting closer to ECL 
and SBCL).

If there are any small projects lying around or pointers I should look 
for this bootstrapping process it'd be appreciated.

Thanks!
Steve

On 12/31/23 8:17 AM, Marius Gerbershagen wrote:
> Dear Jon,
>
> interacting between Lisp and javascript in a browser can be done by 
> directly calling functions from ECL's C interface from javascript or 
> vice-versa using the available methods to call javascript from C and 
> ECL's C foreign function interface. A description for how to call C 
> from javascript and vice-versa can be found at 
> https://emscripten.org/docs/porting/connecting_cpp_and_javascript/Interacting-with-code.html
>
> Another thing to keep in mind is the asynchronous nature of javascript 
> running in a browser which does not integrate easily with the 
> synchronous IO interface of Common Lisp. If you want to keep the Lisp 
> runtime running in the background, waiting for input to arrive, there 
> are two options: either compile with LDFLAGS="-sASYNCIFY" 
> (https://emscripten.org/docs/porting/asyncify.html) or run ECL in a 
> separate thread (by means of a WebWorker) while communicating with the 
> UI thread via Atomics.wait and SharedArrayBuffer's.
>
> For an example of the latter option, you can look at the ECL repl 
> https://repl.chee.party/ that Daniel has linked to or also at 
> https://sourceforge.net/u/mgerbershagen/maxima/ci/emscripten-port/tree/ 
> which contains a very rough early-stage port of the maxima computer 
> algebra system to a browser environment (in particular the wasm 
> subdirectory and the src/ecl-port.lisp file are relevant).
>
> Best regards,
>
> Marius Gerbershagen
>
> Am 30.12.23 um 14:39 schrieb Jón Hallur Haraldsson:
>> Hi,
>>
>> I've been toying around with the idea to run ecl in the browser since 
>> it is now easy to build it using emscripten.
>>
>> I have successfully interacted with the runtime using the extremely 
>> awkward "window.prompt" native javascript pop up.
>>
>> My experience in using ECL is in embedding it in C/C++
>>
>> Has someone successfully used it to run in the browser without using 
>> the "wasm-draw-to-canvas" and "windows.prompt" REPL
>>
>> I'm assuming that this has nothing to do with ECL and is purely how 
>> emscripten works.
>>
>> Can I write a more embedded version which does not require me to 
>> interact through the REPL in the browser.
>>
>> If anyone has done any similar things I'd really like to hear about 
>> them.
>>
>> Kindest regards.
>>
>> Jon Hallur