[R] .Last function in R 4.1.0

[Duncan Murdoch]

And to expand a bit:  only the site file tries to put objects into the 
base package.  The local .Rprofile file would put them into the global 
environment.  So there's still support for .First and .Last, but it has 
changed.

This abuses things a bit, but appears to work in an Rprofile.site file:

assign(".Last", function() if (interactive()) message("Goodbye!"), 
.AutoloadEnv)

The .AutoloadEnv environment is the place that autoload() writes in the 
base package, and it's generally on the search path, so the .Last 
function will be found.  I haven't checked whether it will be run if 
there's also a .Last defined in the global environment.

Duncan Murdoch

On 07/06/2021 10:24 a.m., Bert Gunter wrote:
> According to the News file for 4.1.0 -- you should always check there first
> for such things --
> 
> "The base environment and its namespace are now locked (so one can no
> longer add bindings to these or remove from these)."
> 
> So the docs do seem to need updating.
> 
> Bert Gunter
> 
> "The trouble with having an open mind is that people keep coming along and
> sticking things into it."
> -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )
> 
> 
> On Mon, Jun 7, 2021 at 12:15 AM Paul Louisell <ploutal7 using gmail.com> wrote:
> 
>> Here's my relevant OS / version info for background:
>> R version 4.1.0 (2021-05-18)
>> Platform: x86_64-w64-mingw32/x64 (64-bit)
>> Running under: Windows 10 x64 (build 19043)
>> Here's the problem: I've inserted the following lines *only *into my
>> Rprofile.site file in the etc folder:
>> if(interactive()){
>> .Last=function(){
>> timestamp(stamp=date(), prefix = "##------ ", suffix = " ------##")
>> savehistory()
>> }
>> }
>> This is a basic .Last function to automatically insert a timestamp into the
>> history and save it at the end of an interactive R session. Prior to R
>> 4.1.0, I'd never received an error from these lines. But in version 4.1.0
>> on startup, I get this error:
>> Error: cannot add binding of '.Last' to the base environment
>>
>> And (as expected given the error) the .Last function is not in the
>> workspace:
>>> .Last
>> Error: object '.Last' not found
>> The same thing happens when I start up the 32-bit version. Section 10.8
>> (pg. 54) of *R-intro.pdf *still has the documentation for .First and .Last,
>> and shows examples where you place the function definitions in the
>> Rprofile.site file, as well as other locations. *fullrefman.pdf *also has
>> documentation for these functions. So my question:
>>
>>     - Is this a bug? Or does R not support .First / .Last anymore, and the
>>     documents just need updating?
>>
>> Thanks for your help with this,
>> Paul Louisell
>>
>>          [[alternative HTML version deleted]]
>>
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>> and provide commented, minimal, self-contained, reproducible code.
>>
> 
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
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> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>