[Rd] Querying from R if '--quiet' had been set

[Martin Maechler]

>>>>> Dirk Eddelbuettel 
>>>>>     on Fri, 27 Jun 2025 09:22:36 -0500 writes:

    > The interactive() predicate is helpful in scripted environments. I sometimes
    > also invoke R with '--quiet' and am unable to suppress messages from my own
    > startup code as I cannot test if this flag was set or not. (I can work around
    > it by setting an additional environment variable, but that is clunky.) For me
    > '--quiet' is independent to 'interactive'.

    > R carries the state internally in the integer variable R_Quiet, so a minimal
    > patch only needs to expose an accessor 'quiet()' model after 'interactive()'.
    > Then we get the desired behaviour:

    > ~/svn/r-devel$ RD -q
    >> quiet()
    > [1] TRUE
    >> 

    > and this is similarly FALSE in a normal startup without '-q'.

    > Would this change be of interest?  The patch is just a few lines (but does
    > not yet contain Rd file changes).

As Duncan Murdoch recently explained "here" (in the R mailinglists-verse),
this is indeed a change that only R-core could do .. and I agree
that the change would be relatively small, or rather that most of
the work here would be writing / updating documentation, NEWS, etc.

On the other hand, this functionality has been "implicitly" in R, forever :

  > "--quiet" %in% commandArgs()
  [1] FALSE

... though I agree that using commandArgs() looks a bit "clunky"
and may not always do the expected thing  (embedded use of R;  R
Studio / Positron / ....).

What do you think?

Best,
Martin

    > Cheers, Dirk

    > -- 
    > dirk.eddelbuettel.com | @eddelbuettel | edd using debian.org