[R] example() leaves console prompting to press Enter for new graphs

[Duncan Murdoch]

On 11/01/2010 9:28 AM, Michael Friendly wrote:
> Env: Win XP, R 2.9.2]
>
> It's a minor annoyance, but I find that after I run example(), the 
> console state of prompting to press Enter for
> each new graph remains as it is under example.  It's more annoying that 
> it seems difficult to turn this behavior
> off!
>
> In a fresh session:
>  >  getOption("example.ask")
> [1] "default"
>
> Run an example:
>  > example(plot)
> plot> require(stats)
>
> plot> plot(cars)
> Waiting to confirm page change...
> ...
>
>  > getOption("example.ask")
> [1] "default"
>
> # do another plot:
>  > plot(sin, -pi, 2*pi)
> Waiting to confirm page change...
>  >
>
> # reset option to FALSE
>  > options("example.ask"=FALSE)
>  > plot(sin, -pi, 2*pi)
> Waiting to confirm page change...
>
> # try resetting devAskNewPage
>  > devAskNewPage(ask = NULL)
> [1] TRUE
>  > plot(sin, -pi, 2*pi)
> Waiting to confirm page change...
>  >
>
> There does seem to be code in example to reset this state on exit, and 
> I'm baffled why it doesn't actually
> do it
>
>    ...
>     if (ask == "default")
>         ask <- echo && grDevices::dev.interactive(orNone = TRUE)
>     if (ask) {
>         if (.Device != "null device") {
>             oldask <- grDevices::devAskNewPage(ask = TRUE)
>             if (!oldask)
>                 on.exit(grDevices::devAskNewPage(oldask), add = TRUE)
>         }
>         op <- options(device.ask.default = TRUE)
>         on.exit(options(op), add = TRUE)
>     }
>    ...
>
> So, how can I restore the previous state of plotting w/out prompting?
>
>   


It's not the console state that is left that way, it's the graphics 
window.  If you close it, the next window you open will have the state 
you wanted.  If you had had a window open before you called example, it 
would have been restored. 

Duncan Murdoch