[Rd] A where() functions that does what exists() does but return the environment when object lives?

Henrik Bengtsson henrik.bengtsson at ucsf.edu
Sat Oct 10 01:18:22 CEST 2015


exists("foo", inherits=TRUE) check whether an object named "foo"
exists, and get("foo", inherits=TRUE) retrieves it.  I'm looking for a
similar function to exists() that returns the environment where the
object "foo" exists, iff at all.  If not found, NULL is returned.
Does that exist?


> sample2 <- base::sample
> env <- where("sample2", inherits=TRUE)
> env
<environment: R_GlobalEnv>

Note the difference to:

> obj <- get("sample2", inherits=TRUE)
> environment(obj)
<environment: namespace:base>


> a <- 1
> foo <- function() { b <- 2; list(a=where("a", inherits=TRUE), b=where("b", inherits=TRUE)) }
> foo()
<environment: R_GlobalEnv>
<environment: 0x000000000b7d2798>

> foo()
<environment: R_GlobalEnv>
<environment: 0x000000000b7d23e0>

I do understand that I can implement such a function myself, but I
prefer not to.



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