Unfortunately, changing from the current synchronous to asynchronous processing probably requires changes to the API that would require changes to every existing language mode.
A better way forward may simply be to implement a new block type and then let people gradually convert their language bindings to that. I'll have a look at it for Python. Tom On Thu, Nov 19, 2015 at 5:38 AM, John Kitchin <jkitc...@andrew.cmu.edu> wrote: > Your suggestions sounds possible to me. If you are up for it, I suggest > trying to implement it, and offering it as a patch. > > Tom writes: > > > On Wed, Nov 18, 2015 at 2:55 PM, John Kitchin <jkitc...@andrew.cmu.edu> > > wrote: > > > >> I am pretty sure this is not directly possible right now. > >> > >> Some approaches that resemble it could be: > >> 1. write a src block that will be tangled to a script. > >> 2. tangle the block > >> 3. Run the script in a shell src block with an & so it runs > >> non-blocking. > >> > >> or, use an elisp block like: > >> > >> (org-babel-tangle) > >> (async-shell-command "your script" some-output-buffer) > >> > >> I don't know a way to get continuous updated output in an org-buffer > >> though. > >> > > > > Thanks for the response. I didn't necessarily expect continuous output > into > > the org-buffer itself to work, but I don't see why the Python subprocess > > can't display output as it occurs. After all, it uses comint, and comint > > certainly has facilities for collecting output incrementally while still > > displaying it (cf comint-output-filter-functions). > > > > It looks to me like the problem is that org-babel-comint-with-output > uses a > > "while" loop to collect process output (ob-comint.el:92). At least, it > > could insert the output into the subprocess buffer and make redisplay > > happen. > > > > But I'm not sure why the code is written that way anyway. Long running > > "while" loops in Emacs code don't seem like a good idea to begin with. > > Wouldn't the more natural way for this code to be written in Emacs be the > > following? > > > > - an output filter gets added to the subprocess that collects output > > - the code is sent to the subprocess for execution > > - the command returns > > - the output filter inserts any data it gets into the subprocess buffer, > > into its "results" data structure, perhaps even into the org-buffer > > - when the output filter gets the eoe-indicator, it removes itself from > the > > output filter list and sends a notification that execution has completed > > > > If the user schedules a second block for execution, the simplest thing to > > do is return an error if there is already a block executing for that > > subprocess; alternatively, it could be queued somewhere. > > > > Thanks, > > Tom > > -- > Professor John Kitchin > Doherty Hall A207F > Department of Chemical Engineering > Carnegie Mellon University > Pittsburgh, PA 15213 > 412-268-7803 > @johnkitchin > http://kitchingroup.cheme.cmu.edu >
