Access environment given the ID string

So let me preface this by stating that I found a better, cleaner way around this problem. But this is one of those situations where I'm left slightly determined to figure out what I was trying to do.

trace_back() allows you to access call information and other information through your call stack:

fun1 <- function() {

fun2 <- function() {
  trc <<- rlang::trace_back()


#> List of 4
#>  $ calls  :List of 2
#>   ..$ : language global::fun1()
#>   ..$ : language global::fun2()
#>   .. ..- attr(*, "srcref")= 'srcref' int [1:8] 2 3 2 8 3 8 2 2
#>   .. .. ..- attr(*, "srcfile")=Classes 'srcfilecopy', 'srcfile' <environment: 0x563740a1d5f0> 
#>  $ parents: int [1:2] 0 1
#>  $ ids    : chr [1:2] "0x563740e0f840" "0x563740e0f798"
#>  $ indices: int [1:2] 36 37
#>  - attr(*, "class")= chr "rlang_trace"

Created on 2020-06-04 by the reprex package (v0.3.0)

The ids binding contains the environment IDs. I had a peculiar situation where I had an object in one level of the call stack that I wanted to access - but I couldn't find a clear route to access that environment from the function I was writing in (they were in parallel environments that bother inherited from global).

The rlang::trace_back() call shows me the byte codes of the environments from each level of the call stack. So that begs the question - if I have the byte code of an environment (as a string), can I access that environment using that string?

I acknowledge that this is not a "should do" - but is this a "can do"? I know it would be pretty horrible practice to try to grab objects using a memory address. But is there a way that you can co it using any current tools in R? Or is this something that you'd need to hop under the hood and use C++?

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