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rdplyrmagrittr

Pipe in magrittr package is not working for function rm()

x = 10
rm(x) # removed x from the environment

x = 10
x %>% rm() # Doesn't remove the variable x

1) Why doesn't pipe technique remove the variable?
2) How do I alternatively use pipe and rm() to remove a variable?

Footnote: This question is perhaps similar to Pipe in magrittr package is not working for function load()

Solution

  • Use the %<>% operator for assigning the value to NULL

    x %<>% 
   rm()

    In the pipe, we are getting the value instead of the object. So, by using the %<>% i.e. in place compound assignment operator, the value of 'x' is assigned to NULL

    x
#NULL

    If we need the object to be removed, pass it as character string, feed it to the list argument of rm which takes a character object and then specify the environment

    x <- 10
"x" %>% 
    rm(list = ., envir = .GlobalEnv)

    When we call 'x'

    x

    Error: object 'x' not found

    The reason why the ... doesn't work is that the object . is not evaluated within the rm

    x <- 10
"x" %>%
    rm(envir = .GlobalEnv)

    Warning message: In rm(., envir = .GlobalEnv) : object '.' not found

    Another option is using do.call

    x <- 10
"x" %>%
   list(., envir = .GlobalEnv) %>% 
   do.call(rm, .)
x

    Error: object 'x' not found