Is the R help file for `<< -` really correct?

Question

I am trying to explain the scope and debugging for a presentation on R. I read the help file for <<-and saw how it says this:

The <<and →> operators are usually used only in functions and cause a search in the parent environments for the existing definition of the assigned variable. If such a variable is found (and its binding is not blocked), then its value is overridden, otherwise the assignment is performed in the global environment.

But I don’t think it fully describes what he is doing <<-. Here is the function:

do.func <- function() {
  x <- 1
  {
    x<<-0
  }
  print(x)
}

do.func()
x

produces this conclusion:

>     do.func()
[1] 1
>     x
[1] 0

It seems to be <<-doing right in the global environment. Is it correct?

Answer 1

.

:

do.func <- function() {
  `<-`(x, 1)
  `{`(x <<- 0)
  print(x)
}

( ), , . { :

`{` (`<<-`(x, 0) )

:

`<<-`(variable, value)

. :

> ( `<<-`(x, 2) )
[1] 2

- , x ( ). , :

{
  x<<-0
}  

x , x {, .

. :

help(`{`)