Re: [O] python sessions

[Andreas Röhler]

Am 20.03.2013 04:07, schrieb Nick Dokos:
> John Hendy <address@hidden> wrote:
>
> > On Tue, Mar 19, 2013 at 4:40 PM, Gary Oberbrunner <address@hidden> wrote:
> > > I must be failing to understand something.  I'm running Emacs 24.3 on
> > > Windows, with latest trunk org-mode.  I can't get python functions to
> > > persist across blocks in session mode.  Here's my foo.org:
> > >
> > > ===============
> > >
> > > * My Document
> > > #+BEGIN_SRC python :exports results :results output :session
> > > def foo(x):
> > >    return x+1
> > > print "hi"
> > > #+END_SRC
> > >
> > > #+RESULTS:
> > > : hi
> > >
> > > #+BEGIN_SRC python :exports results :results output :session
> > > print foo(100)
> > > print "bye"
> > > #+END_SRC
> > >
> > > ========================
> > >
> > > In session mode, shouldn't foo be defined in the second python block?  When
> > > I export this, I get "NameError: name 'foo' is not defined"
> > >
> > > I may be doing something wrong, because if I name my python session, I never
> > > see a buffer of that name, and I expected to.  Any help?
> > >
> > > --
> > > Gary
> >
> > You should probably post your babel configuration from .emacs. This
> > works for me (mostly). I'm using python 3.3 and so the print function
> > has changed to requiring parentheses. I can switch to a buffer called
> > *Python*, however, and =print("hi")= works fine.
> >
> > If I change to =print(foo(100))=, I get 101 in the #+RESULTS block.
>
> I don't - I get the same error as Gary.
>
> And looking at the code of org-babel-python-initiate-session-by-key,
> I don't understand how it's supposed to work: python-buffer is nil
> to begin with; the cond takes the first branch and starts a python session.
> When we come to
>
>        (setq org-babel-python-buffers
>             (cons (cons session python-buffer)
>                   (assq-delete-all session org-babel-python-buffers)))
>
> python-buffer is still nil, so we are cooked.
>
> Maybe python-buffer was set as a side-effect of run-python in earlier
> versions of emacs? If so, it does not seem to be the case now.
>
> Nick
>
> Org-mode version 8.0-pre (release_8.0-pre-144-g855dcf.dirty @ 
> /home/nick/elisp/org-mode/lisp/)
> GNU Emacs 24.3.50.2 (x86_64-unknown-linux-gnu, GTK+ Version 2.24.4) of 
> 2012-12-29 on alphaville

AFAIU :session is broken, because Python shell as opened by run-python or 
py-shell isn't used by ob-babel.
Seems ob-babel sends it's code w/ an own shell command, thus opening a new 
python shell internally every time.

Did :session ever work? Then I might be wrong with this comment.

Andreas