Re: python sessions

["Andreas Röhler" <andreas.roehler@easy-emacs.de>]

Am 25.03.2013 17:43, schrieb Eric Schulte:
> John Hendy <jw.hendy@gmail.com> writes:
>
>> On Mon, Mar 25, 2013 at 11:01 AM, Ista Zahn <istazahn@gmail.com> wrote:
>>> On Mon, Mar 25, 2013 at 11:40 AM, Eric Schulte <schulte.eric@gmail.com> wrote:
>>>> John Hendy <jw.hendy@gmail.com> writes:
>>>>
>>>>> On Sun, Mar 24, 2013 at 9:38 PM, Nick Dokos <nicholas.dokos@hp.com> wrote:
>>>>>> Eric Schulte <schulte.eric@gmail.com> wrote:
>>>>>>
>>>>>>>>
>>>>>>>>  From participating in evaluating code throughout the discussion and
>>>>>>>> catching the comments throughout, I'd say yes, at least in terms of
>>>>>>>> how other babel languages function. In other words =#+begin_src R
>>>>>>>> :session foo= creates an R session named "foo" whereas doing the same
>>>>>>>> with =python= instead of =R= does not yield a named session.
>>>>>>>>
>>>>>>>>  From what others experienced, however, the functionality was working
>>>>>>>> correctly (results were persistent across blocks and two differently
>>>>>>>> names blocks created two different sessions), just not named
>>>>>>>> correctly.
>>>>>>>>
>>>>>>>
>>>>>>> See the cond form starting at line 169 in ob-python.el.  Different
>>>>>>> session functionality is used based on the `org-babel-python-mode'
>>>>>>> variable, and on the version of Emacs in use (prior to 24.1 or not).
>>>>>>>
>>>>>>> The branch taken when `org-babel-python-mode' equals 'python is
>>>>>>> certainly broken, as it never saves the name of the newly created
>>>>>>> buffer, so session re-use and use of multiple named sessions probably
>>>>>>> works only when `org-babel-python-mode' equals 'python-mode.
>>>>>>>
>>>>>>
>>>>>> That's me: org-babel-python-mode's value is python, so it's no wonder
>>>>>> it's broken given what Eric says. I'm on emacs 24.3.50 where there is
>>>>>> python.el but no python-mode.el. I tried the "cheap" workaround of
>>>>>> switching the value to python-mode, but that does a (require
>>>>>> 'python-mode) somewhere, so that option is out as well.
>>>>>
>>>>> I'm on Emacs 24.3.1 and have no python-mode.el, either (only
>>>>> python.el). My setup is working correctly (again, with the caveat of
>>>>> not having named sessions).
>>>>>
>>>>
>>>> It sounds like we have the same setup, and the following un-named
>>>> session example does not work for me.  The first code block evaluates
>>>> successfully, but it doesn't appear to be having any impact on the
>>>> default session (e.g., in the *Python* buffer).
>>>>
>>>>      Returns the value of x as expected.
>>>>
>>>>      #+begin_src python :session
>>>>        x = 1
>>>>        return x
>>>>      #+end_src
>>>>
>>>>      #+RESULTS:
>>>>      : 1
>>>>
>>>>      #+begin_src python :session
>>>>        return x
>>>>      #+end_src
>>>>
>>>>      #+RESULTS:
>>>>
>>>> The second code block /should/ have access to the x variable defined
>>>> previous, but instead it throws an error because x is undefined.
>>>>
>>>> Currently I'd say session support for python is completely broken.
>>>
>>> As of this morning I've joined the "it does not work" crowd. Python
>>> sessions worked for me last week, but are now completely broken for me
>>> in the way Eric and others describe.
>>
>> Interesting... checked out back to that commit
>> (eff59a15d76647ce8282626b9eb463dc3706d56e) and it still doesn't work.
>> On a whim, I checked my pacman log (Arch's install system) and
>> coincidentally on Mar 20 /after/ I wrote that post in which things
>> work, I ran a system package update.
>>
>> $ grep -i emacs /var/log/pacman.log
>>
>> [2013-03-20 12:51] upgraded emacs (24.2-4 -> 24.3-1)
>>
>> Using the Arch Rollback Machine, I downloaded Emacs 24.2.4 and
>> downgraded (also required downgrading imageMagick from 6.8.3.10 ->
>> 6.8.2.3). Now it works again (refer to the reproducible example from
>> the mailing list post):
>> - http://www.mail-archive.com/emacs-orgmode@gnu.org/msg68238.html
>>
>> Eric, your example fails for me. I get:
>>
>
> Yes, because my example only works in external (non session) execution
> with the current buggy code, where as your example works with session
> execution in the old working code.
>
>>
>>>>> x = 1
>>>>> return x
>>    File "<stdin>", line 1
>> SyntaxError: 'return' outside function
>>
>> This works, hoever:
>>
>> #+begin_src python :session
>>        x = 1
>>        x
>> #+end_src
>>
>> #+RESULTS:
>> : 1
>>
>> #+begin_src python :session
>>        x
>> #+end_src
>>
>> #+RESULTS:
>> : 1
>>
>> So, with emacs 24.2.4 and current Org-mode (pulled just now) and clean
>> make, *both* named and un-named sessions work for me on Arch Linux.
>>
>
> Aha! Thanks for sleuthing this out.  So the problem lies in changes to
> the python.el distributed with Emacs.  I don't suppose we can ask
> whoever made these changes to python.el to fix the breakage they've
> caused in Org-mode?
>
> Thanks,
>

Please give me some time still to investigate. Still doubt it's python.el
But if yes, probably will be able to tell more.

Best,

Andreas