[R] provide extra variables to environment in call

[Liaw, Andy]

Not an direct answer to your question, but why not do something like:

> f <- function() x + 1
> x <- 10
> f()
[1] 11
> g <- function(x, ...) {
+     my.f <- f
+     formals(my.f) <- c(list(x=NULL), formals(f))
+     my.f(x, ...)
+ }
> g(5)
[1] 6

Andy

> From: Khamenia, Valery
> 
> Hi all,
> 
> Situation: 
> 
>  there is a function `f' already defined by someone and 
>  provided in package. `f' looks like that:
> 
>   f <- function() {
>     x+1
>   }
> 
>  i.e. `f' is not closed i.r.t. term `x'
> 
>  now I have my own function `g', where I'd like
>  to override variable `x' while calling `f':
> 
>   x <- "dummy gloabal value"
> 
>   g <- function() {
>     x <- 42
>     eval(f(), environment()) # how to make loacl `x' visible in `f'?
>   }
> 
>   g() # => Error in x + 1 : non-numeric argument to binary operator
> 
> Here comes the question:
> 
>  What is the right way to call `f' in order to override 
>  global value of `x' with the local value defined within 
>  of function `g' ?
> 
> I see that i've missed something in docs for 
> eval/environments and related.
> 
> Thank you in advance.
> --
> Valery.
> 
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