[R] control enviromnet

[Roger D. Peng]

I think you can use exists() in combination with ls(envir = environment()).

-roger

facS93 at hampshire.edu wrote:

> thanks Roger, 
> this doesn't do exactly what I want, which I didn't explain clearly enough in 
> the original post. I want to have a check mechanism to find whether there are 
> variables in the function that are not "locally" defined, in which case I 
> wouldn't know in advance what they are - well, I probably should because I am 
> writing the function. It's just that when the function gets kind of large, and 
> I am testing it as I am building it, it's easy to lose track of all these 
> variables.
> 
> thanks,
> 
> Fang
> 
> Quoting "Roger D. Peng" <rpeng at jhsph.edu>:
> 
> 
>>I think you want something like
>>
>>exists("x", where = environment(), inherits = FALSE)
>>
>>-roger
>>
>>facS93 at hampshire.edu wrote:
>>
>>>Hi all:
>>>
>>>I would like to implement an option in my function so that it warns me of
>>
>>any 
>>
>>>variables that are not defined in the current environment - if it needs to
>>
>>>look up variables in the parent frame, it tells me so. 
>>>
>>>The following is an example and it does what I want, and I'd rather have
>>
>>the 
>>
>>>environment control option inside this function instead of outside. Any
>>
>>help 
>>
>>>would be greatly appreciated.
>>>
>>>x = 1
>>>test = function(y) {
>>> ans = y + x;
>>> return(ans);
>>>}
>>>environment(test)=NULL
>>>test(y = 1)
>>>
>>>Thanks much!
>>>
>>>Fang
>>>
>>>______________________________________________
>>>R-help at stat.math.ethz.ch mailing list
>>>https://stat.ethz.ch/mailman/listinfo/r-help
>>>PLEASE do read the posting guide!
>>
>>http://www.R-project.org/posting-guide.html
>>
> 
> 
>