[R] Is there a way to figure out what nonlocal variables and functions have been used in a function?

[blue sky]

On Fri, Feb 12, 2010 at 1:36 PM, Sharpie <chuck at sharpsteen.net> wrote:
>
>
> blue sky wrote:
>>
>> x=10
>> f=function() {print('in f')}
>> g=function() {f(); print(x)}
>> g()
>>
>> Suppose I have the above code, I want to know what functions and
>> variables have been used in the function g (in this case, f and x). Is
>> there a function to do so?
>>
>>
>
> Try findGlobals() from the codetools package:
>
>  require( codetools )
>
>  findGlobals( g )
>  [1] "{"     "f"     "print" "x"

I don't what '{' and functions available in R libraries. I can
manually exclude '{'. Is there an easy way to exclude the functions
from R libraries?