Eli Zaretskii <eliz@gnu.org> writes:

>> From: John Shahid <jvshahid@gmail.com>
>> Cc: rudalics@gmx.at, 31325@debbugs.gnu.org, monnier@iro.umontreal.ca
>> Date: Sun, 01 Jul 2018 17:18:08 +0000
>>
>> >> It just occurred to me that this change will break backward
>> >> comparability for those who bind some key to the `recenter' command,
>> >> since now the second argument will always be nil and thus won't
>> >> redisplay.  Should we also change the interactive form of recenter to
>> >> use "p" for the second argument?  That way the second arg is never nil
>> >> when used interactively.
>> >
>> > I think you are right.
>> >
>> > Alternatively, we could simply make 'recenter' behave specially in
>> > interactive invocations.  But in any case, incompatible changes in
>> > behavior are bad, and should be avoided.
>>
>> I am happy to make the change. Should we just revert this patch and
>> instead of adding a new argument change the behavior of`recenter' to
>> redraw if called interactively ?
>>
>> How can we determine from C whether the function is called interactively
>> ? Is it ok to use `called-interactively-p' ?
>
> That'd be gross, I think.  Going through the interactive spec, as you
> suggested originally, should be much simpler.

Updated the interactive spec in the attached patch and made the
necessary changes to the manual and documentation.  I also missed a
place where `recenter-top-bottom' was calling `recenter' without passing
a non-nil value for REDISPLAY that I also fixed in the attached patch.

Let me know what you think.

Thanks,