[R] Function assignment

[peter dalgaard]

On 26 Jul 2014, at 17:01 , Jeff Newmiller <jdnewmil at dcn.davis.ca.us> wrote:

> What an awful idea... that would lead to incredibly hard-to-debug programs. No, you cannot do that. What kind of problem has led you to want such a capability? Perhaps we can suggest a simpler way to think about your problem.

I agree that this is a silly idea, but I actually thought that it could be done by clever manipulation of the call stack. It can if you do the assignment with assign():

> foo <- function()sys.calls()[[1]][[2]]
> assign("z", foo())
> z
[1] "z"
> assign("bah", foo())
> bah
[1] "bah"

but if you do x <- foo(), there is no mention of x or "x" in sys.calls().

Anyways, functions that assume being called in a specific are asking for trouble in all cases where they get called differently.

-pd



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> 
> On July 26, 2014 5:29:59 AM PDT, Florian Ryan <florian.ryan at aim.com> wrote:
>> Hello,
>> 
>> I would like to use the variable name which i assign the return value
>> of a function in a function. Is that possible?
>> e.g.
>> 
>> foo <- function(){
>>   some not to me known R magic
>> }
>> 
>> myVariableName <- foo()
>> myVariableName
>> [1] "myVariableName"
>> 
>> Hope someone can help me.
>> 
>> Thanks
>> Florian
>> 
>> 	[[alternative HTML version deleted]]
>> 
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> 
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-- 
Peter Dalgaard, Professor,
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com