R help - Mar 2022 - Creating and manipulating environment within function

Hi

I am trying to create a set of functions to create and manipulate objects within
a dedicated environment, which I was hoping to put directly under the global
environment. However, my implementation (see code below) is facing some scoping
issues: the environment created by one function does not appear to be accessible
from outside the function.

What would be the proper way to create a manipulation an environment in
different functions?

Thanks

```
create_e1 <- function(){
  e1 <- new.env(parent = globalenv())
  exists('e1', mode = 'environment')
}
create_e1()

manipulate_e1 <- function(){
  if ( exists('e1', mode = 'environment') ) {
    assign(a, 1, envir = e1)
    TRUE
  } else {
    FALSE
  }
}

exists('e1', envir = globalenv())
manipulate_e1()
```
This message is sent to you because your email address is the contact email
address provided for receiving messages related to: our products or services
purchased, or information requested, from us; and/or evaluating or having
entered into a business relationship with us. Visit our privacy policy at
https://www.simulations-plus.com/privacy-policy/ to learn more about how we use
your personal information and your rights regarding your personal information,
including how to opt out of receiving marketing emails from us.

Hello,

Use ?assign instead. And there was a bug in manipulate_e1, it would 
throw an error a not found.


create_e1 <- function(){
   assign("e1", new.env(), envir = globalenv())
   exists('e1', mode = 'environment')
}

manipulate_e1 <- function(a){
   if ( exists('e1', mode = 'environment') ) {
     assign(a, 1, envir = e1)
     TRUE
   } else {
     FALSE
   }
}

create_e1()
#> [1] TRUE

exists('e1', envir = globalenv())
#> [1] TRUE

x <- "vec"
e1$vec
#> NULL
manipulate_e1(x)
#> [1] TRUE
e1$vec
#> [1] 1


Hope this helps,

Rui Barradas

?s 21:29 de 30/03/2022, Sebastien Bihorel escreveu:
> Hi
> 
> I am trying to create a set of functions to create and manipulate objects
within a dedicated environment, which I was hoping to put directly under the
global environment. However, my implementation (see code below) is facing some
scoping issues: the environment created by one function does not appear to be
accessible from outside the function.
> 
> What would be the proper way to create a manipulation an environment in
different functions?
> 
> Thanks
> 
> ```
> create_e1 <- function(){
>    e1 <- new.env(parent = globalenv())
>    exists('e1', mode = 'environment')
> }
> create_e1()
> 
> manipulate_e1 <- function(){
>    if ( exists('e1', mode = 'environment') ) {
>      assign(a, 1, envir = e1)
>      TRUE
>    } else {
>      FALSE
>    }
> }
> 
> exists('e1', envir = globalenv())
> manipulate_e1()
> ```
> This message is sent to you because your email address is the contact email
address provided for receiving messages related to: our products or services
purchased, or information requested, from us; and/or evaluating or having
entered into a business relationship with us. Visit our privacy policy at
https://www.simulations-plus.com/privacy-policy/ to learn more about how we use
your personal information and your rights regarding your personal information,
including how to opt out of receiving marketing emails from us.
> 
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.