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

[Michael Friendly]

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?


-- 
Michael Friendly     Email: friendly at yorku.ca 
Professor, Psychology Dept.
York University      Voice: 416 736-5115 x66249 Fax: 416 736-5814
4700 Keele Street    http://www.math.yorku.ca/SCS/friendly.html
Toronto, ONT  M3J 1P3 CANADA