[Rd] how to start local scope?

[Duncan Murdoch]

On 7/27/2006 8:16 AM, Tamas K Papp wrote:
> How can I start a local scope inside an R function?  Eg in
> 
>> b
> Error: object "b" not found
>> f <- function() {
> +   {
> +     b <- 1
> +   }
> +   b+2
> + }
>> f()
> [1] 3
> 
> I would like f() to report an error, not finding b.  I am thinking
> about something like let in Scheme/Lisp.

The local() function does this:

 > f <- function() {
+   local({ b <- 1 })
+   b + 2
+ }
 > f()
Error in f() : object "b" not found