Carson Farmer wrote:
> Laurent (et al.),
>> Right now having R_Visible as a global is ok for 2.0.x, but for 2.1.x
>> I will be considering whether a call to an invisibly returning
>> function should return None to Python, or else (visibility attribute
>> with the returned objects, etc...).
> The output of withVisible in R simply returns a list with a) the
> returned value, and b) its visibility:
>
> > withVisible( a <- c(1, 2, 3, 4, 5, 6) )
> $value
> [1] 1 2 3 4 5 6
>
> $visible
> [1] FALSE
>
> > withVisible( c(1, 2, 3, 4, 5, 6) )
> $value
> [1] 1 2 3 4 5 6
>
> $visible
> [1] TRUE
>
>
> something similar might be useful in this case as well?
Yes, although it might just be implicit.
In the case of implementing a console for an embedded R, looking what is
the status of the R C-level global variable R_Visible is going to be
enough. An if/else branching will decide whether something is returned
to the console or not (just like in the example of a python
with_visible() function below).
R's withVisible() is returning the result of the function call together
with a snapshot of R_Visible upon return (I think - and I am seeing this
as a confirmation that R_Visible exposed to Python should be a read-only
thing for now).
Implementing something like it would be straightforward (example from a
global)
def with_visible(function, *args, **kwargs):
sexp = function(*args, **kwargs)
if rpy2.rinterface.r_visible:
return sexp
else:
return None
but my concern is over possible object duplication when returning from
'function(*args, **kwargs)' (not necessarily the case, but if something
is invisible and I can't get rid of copying this is annoying - I need
more thinking about this). Anyway, there is still time to think about
it, I don't expect much visibility about a possible schedule for 2.1.0
before weeks.
L.
> Carson
>
------------------------------------------------------------------------------
Open Source Business Conference (OSBC), March 24-25, 2009, San Francisco, CA
-OSBC tackles the biggest issue in open source: Open Sourcing the Enterprise
-Strategies to boost innovation and cut costs with open source participation
-Receive a $600 discount off the registration fee with the source code: SFAD
http://p.sf.net/sfu/XcvMzF8H
_______________________________________________
rpy-list mailing list
rpy-list@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/rpy-list
