Error in NextMethod() : generic function not specified

[JanMarvin]

After the update to R6 2.6.0 I'm seeing this error a lot in the Rstudio console. Using the example from here

Queue <- R6Class("Queue",
  public = list(
    initialize = function(...) {
      for (item in list(...)) {
        self$add(item)
      }
    },
    add = function(x) {
      private$queue <- c(private$queue, list(x))
      invisible(self)
    },
    remove = function() {
      if (private$length() == 0) return(NULL)
      # Can use private$queue for explicit access
      head <- private$queue[[1]]
      private$queue <- private$queue[-1]
      head
    }
  ),
  private = list(
    queue = list(),
    length = function() base::length(private$queue)
  )
)

q <- Queue$new(5, 6, "foo")

Now type the following and press any key. Each key creates a new Error in NextMethod() : generic function not specified

q$

Saw this in Rstudio on Windows R 4.1.2, but also on Rstudio (2024.12.0 Build 467) and R 4.4.2 with openxlsx2 (JanMarvin/openxlsx2#1268)

Is there any way to stop this?

[wch]

Edit: I previously posted a message that said I wasn't able to reproduce it, but I had neglected to update R6 to 2.6.0.

I am able to reproduce this in RStudio. But the problem doesn't happen in R in the terminal.

[JanMarvin]

Thanks!

[vladimirobucina]

@wch I'm not sure if this is related, but it is strange to me that it occurred recently and also with R6 version 2.6.0. So when I go back to version 2.5.1 autocompletion works, but with the newest version it stops.

Here some more info:

• R version: 4.4.3
• Positron version: 2024.12.0 (Universal) build 41
• Operating System: macOS Sequoia 15.3.1

Btw, I'm using Air.

[wch]

@vladimirobucina I think I'm able to reproduce the problem: with Positron and R6 2.6.1, tab-completion doesn't seem to work. Can you file a new issue for this?

Reproducible example:

library(R6)
AC <- R6Class("AC",
    public = list(
        x = 1
    )
)

a <- AC$new()

# Press <tab> below
a$