Re: :session question

[Eric Schulte <schulte.eric@gmail.com>]

Achim Gratz <Stromeko@nexgo.de> writes:

> Eric Schulte writes:
>> If you mean that there should be new syntax for setting header arguments
>> on a file or sub-tree basis w/o using file local variables, I'd be happy
>> to apply a patch.
>
> I'm thinking that something like
>
> #+PROPERTY: header-args:R :session "*R*" :exports none
>
> should work.

I hate to change syntax, but the syntax you mention above does look both
appealing and natural.  Even with working file local variables [1].

> I've checked that the property interface returns the data as expected,
> but I haven't implemented anything yet.  It does not seem to be an
> overly difficult endeavour, however.
>

That is very good news.  With that portion working I would agree that
this should be a fairly straightforward task.

>
>>> But importantly, there should be no way to set a default session name
>>> without also specifying the language, regardless of which way one
>>> tries to set this up.
>>
>> If you can think of a clean way to implement this then we should go for
>> it.  I doubt many existing configurations rely on this behavior.
>
> General settings for all languages should be effected by
>
> #+PROPERTY: header-args :results value :exports none
>
> and there'd be a list of header arguments (or specific values) that are
> either ignored or warned about when not associated with a particular
> language.
>
> BTW, I think the current property syntax for header arguments should be
> deprecated since it is the only place where the leading ":" is missing
> for those.
>
> Comments, thoughts?
>

I think these are great ideas.  Personally I'd love to see them
implemented.  Unfortunately I don't have time to work on an
implementation currently.  I'm surprised that none of the users who
motivated this discussion have chimed in.  Their opinions may be more
valuable than my own in this regard (as I'm not a heavy #+Property
user).

Thanks for the clean and initially tested implementation idea!

>
>
> Regards,
> Achim.


Footnotes: 

[1]  Thanks to Bastien my patch allowing variables like
     `org-babel-default-header-args:R' to be set file-local has been
     applied to Emacs.

-- 
Eric Schulte
http://cs.unm.edu/~eschulte