You are right,

in the first time that I read the post, I understand incorrectly the
question.



On Wed, Sep 9, 2009 at 12:09 PM, Simon Urbanek
<simon.urba...@r-project.org>wrote:

>
> On Sep 9, 2009, at 9:40 , Henrique Dallazuanna wrote:
>
>  If I understand your question, you can get the environment with sys.frame:
>>
>> f <- function(code){
>>   print(sys.frame())
>>
>
> ^-- this will always return R_GlobalEnv (see ?sys.frame - which = 0 by
> default) regardless of the function and promise.
>
> Also the question was about the environment of the promise, not the
> function. Technically a promise can be evaluated anywhere since it ignores
> the evaluation environment and will use its creation environment which is
> what Hadley was trying to get at (and as Duncan was saying it's not
> something that is or should be available at R level as it's an internal
> implementation detail).
>
> Cheers,
> Simon
>
>
>    force(code)
>> }
>>
>> f({
>> a <- 1
>> b <- 2
>> })
>>
>> On Wed, Sep 9, 2009 at 10:30 AM, Hadley Wickham <had...@rice.edu> wrote:
>>
>>  Hi all,
>>>
>>> Is it possible to determine the environment in which a promise will be
>>> evaluated?  e.g.
>>>
>>> f <- function(code) { force(code) }
>>> f({
>>> a <- 1
>>> b <- 2
>>> })
>>>
>>> Is there any way to tell from within f that a and b will be created in
>>> the global environment?
>>>
>>> Thanks,
>>>
>>> Hadley
>>>
>>> --
>>> http://had.co.nz/
>>>
>>> ______________________________________________
>>> R-devel@r-project.org mailing list
>>> https://stat.ethz.ch/mailman/listinfo/r-devel
>>>
>>>
>>
>>
>> --
>> Henrique Dallazuanna
>> Curitiba-Paraná-Brasil
>> 25° 25' 40" S 49° 16' 22" O
>>
>>        [[alternative HTML version deleted]]
>>
>> ______________________________________________
>> R-devel@r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-devel
>>
>
>


-- 
Henrique Dallazuanna
Curitiba-Paraná-Brasil
25° 25' 40" S 49° 16' 22" O

        [[alternative HTML version deleted]]

______________________________________________
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel

Reply via email to