R devel - Nov 2017 - ans[nas] <- NA in 'ifelse' (was: ifelse() woes ... can we agree on a ifelse2() ?)

Removal of
ans[nas] <- NA
from the code of function 'ifelse' in R is not committed (yet). Why?

--------------------------------------------
On Mon, 28/11/16, Martin Maechler <maechler at stat.math.ethz.ch> wrote:

 Subject: Re: [Rd] ifelse() woes ... can we agree on a ifelse2() ?

 Cc: R-devel at r-project.org, maechler at stat.math.ethz.ch
 Date: Monday, 28 November, 2016, 10:00 PM
 
>>>>> Suharto Anggono Suharto Anggono via R-devel <r-devel at
r-project.org>
>>>>>     on Sat, 26 Nov 2016 17:14:01 +0000 writes:
...


    > On current 'ifelse' code in R:

    > * The part
    > ans[nas] <- NA
    > could be omitted because NA's are already in place.
    > If the part is removed, variable 'nas' is no longer used.

I agree that this seems logical.  If I apply the change, R's own
full checks do not seem affected, and I may try to commit that
change and "wait and see".


...

>>>>> Suharto Anggono Suharto Anggono <suharto_anggono at
yahoo.com>
>>>>>     on Sat, 4 Nov 2017 12:11:48 +0000 writes:
    > Removal of
    > ans[nas] <- NA
    > from the code of function 'ifelse' in R is not committed (yet).
Why?

because I have been using it in my version of R-devel for this whole
year, but have forgotten to commit it.

Thank you for the reminder.  I have committed it now :

------------------------------------------------------------------------
r73681 | maechler | 2017-11-06 15:39:20 +0100 (Mon, 06 Nov 2017) | 3 lines

drop extraneous line, as suggested by Suharto Anggono, and as
"promised" on R-devel list, Nov 26, 2016

------------------------------------------------------------------------


    > On Mon, 28/11/16, Martin Maechler <maechler at stat.math.ethz.ch>
wrote:

    > Subject: Re: [Rd] ifelse() woes ... can we agree on a ifelse2() ?
    > To: "Suharto Anggono" <suharto_anggono at yahoo.com>
    > Cc: R-devel at r-project.org, maechler at stat.math.ethz.ch
    > Date: Monday, 28 November, 2016, 10:00 PM
 
>>>>> Suharto Anggono Suharto Anggono via R-devel <r-devel at
r-project.org>
>>>>>     on Sat, 26 Nov 2016 17:14:01 +0000 writes:
    > ...


    >> On current 'ifelse' code in R:

    >> * The part
    >> ans[nas] <- NA
    >> could be omitted because NA's are already in place.
    >> If the part is removed, variable 'nas' is no longer used.

    > I agree that this seems logical.  If I apply the change, R's own
    > full checks do not seem affected, and I may try to commit that
    > change and "wait and see".

    > ...