[Rd] Should invisible() get signature x=NULL?
m@ech|er @end|ng |rom @t@t@m@th@ethz@ch
Tue Aug 2 09:26:12 CEST 2022
>>>>> Duncan Murdoch
>>>>> on Mon, 1 Aug 2022 20:08:53 -0400 writes:
> On 01/08/2022 6:27 p.m., Michael Chirico via R-devel
>> I think most experienced R users are familiar with
>> return(invisible()) being used as shorthand for
> I'm not sure that's true... the R sources themselves are
> inconsistent about using invisible() vs invisible(NULL).
Well, they *are* identical in what they return, but to me there *is* a
stylistic difference: The latter emphasizes the return value to
>> However, this NULL default is not documented anywhere --
>> we have to dive into src/main/print.c:do_invisible to
>> source this behavior.
>> Is this lack of documentation intentional? Otherwise,
>> should the signature be updated to reflect this default?
>> invisible <- function(x = NULL) .Primitive("invisible")
>> Otherwise, should this default be mentioned in ?invisible
> But documenting it seems wise.
> Duncan Murdoch
I prefer to agree with Michael that the "fake" argument list (*)
should be updated to 'x = NULL'.
*) Primitive functions have no formal arguments. We have
provided artificially constructed formal arguments mainly for
printing, only "relatively recently".
E.g., in R 2.0.0, we still had
ETH Zurich and R Core team
More information about the R-devel