Message-ID: <3cfdc485-3c05-45e8-93e1-1524189d6d7c@auckland.ac.nz>
Date: 2019-07-15T00:40:38Z
From: Rolf Turner
Subject: [R-pkg-devel] Warning about "serialize/load".
In-Reply-To: <21c0b6f4-969c-c226-0948-46bf2b104f1b@gmail.com>
On 15/07/19 12:19 PM, Duncan Murdoch wrote:
> On 14/07/2019 7:52 p.m., Rolf Turner wrote:
>>
>> In a package (say "clyde") that I am building I save a number of
>> datasets in clyde/data via something like:
>>
>> save(melvin,file="~/<whatever>/clyde/data/melvin.rda")
>>
>> When I build "clyde" I now get warnings like unto:
>>
>>> WARNING: Added dependency on R >= 3.5.0 because serialized objects in
>>> serialize/load version 3 cannot be read in older versions of R.
>>> File(s) containing such objects: 'clyde/data/melvin.rda'
>>
>> If I put the argument "version=2" into my save() call, the warnings go
>> away.
>>
>> What are the implications of this?
>>
>> What are the consequences/what is the downside of setting version=2?
>>
>> What are the consequences/what is the downside of adding the dependency
>> on R >= 3.5.0 into my DESCRIPTION file?
>
> The main consequence of setting the R version is that nobody using an
> older version could use your package.
>
> I'd suggest this is a good thing, unless you plan to test your package
> with those old versions.? People should be nudged to upgrade.
Indeed. I agree.
> However, some people are stuck on old versions, and they really would miss
> out on clyde.
And I'd hate that!!! :-)
> I think Travers pointed out the main consequence of forcing version=2:
> some things that are very compact in the next version might take a lot
> more space in version=2, e.g. x <- 1:1000000.
I don't think that space is a major issue. I managed to tot up the
total size of the data sets, using object.size() and I get 1219824
bytes, i.e. about one and a quarter megabytes. I don't think that's a
worry, so I think I'll stick with version=2.
Thanks Duncan.
cheers,
Rolf
--
Honorary Research Fellow
Department of Statistics
University of Auckland
Phone: +64-9-373-7599 ext. 88276