Thanks Duncan for a clear argument about the "why".
The suggestion of R --vanilla started a train of thought that one could do
something like
clearws <- function(){ # Try to clear workspace
tmp <- readline("Are you sure you want to clear the workspace? ")
print(tmp)
if ( substr(toupper(tmp),1,1) != "Y" ){
return(0)
}
# rm(tmp)
tgt<-parent.env(environment())
print(ls(tgt))
rm(list = ls(tgt, all.names = TRUE),envir=tgt) #will clear all objects
includes hidden objects.
gc() #free up memrory and report the memory usage.
# What should we return?
# Can we offer interactive control?
# How about packages?
}
and call clearws() at the start of an example.
Contact me off-list if you have suggestions for improving this. I'd like to be
able to preface
examples with such a function that would render the session "vanilla" but from
inside. That means
removing packages that might have altered / replaced / masked standard
functions. That might not
be possible, but the idea is attractive to me as someone who mostly uses R in
tests of tools that
get used by others.
Best, JN
On 2021-01-21 6:05 p.m., Duncan Murdoch wrote:
> On 21/01/2021 5:20 p.m., J C Nash wrote:
>> In a separate thread Jeff Newmiller wrote:
>>> rm(list=ls()) is a bad practice... especially when posting examples. It
>>> doesn't clean out everything and it removes
>>> objects created by the user.
>>
>> This query is to ask
>>
>> 1) Why is it bad practice to clear the workspace when presenting an example?
>> I'm assuming here that people who will try R-help examples will not run them
>> in the
>> middle of something else, which I agree would be unfortunates.
>
> I think that's exactly the concern. I doubt it would have happened in this
> instance, but in other cases, people might
> copy and paste a complete example before reading it. It's safer to say:
> "Run this code in a clean workspace:", rather
> than cleaning it out yourself.
>
> Duncan Murdoch
>
>
> However, one of the
>> not very nice aspects of R is that it is VERY easy to have stuff hanging
>> around (including
>> overloaded functions and operators) that get you into trouble, and indeed
>> make it harder
>> to reproduce those important "minimal reproducible examples". This includes
>> the .RData
>> contents. (For information, I can understand the attraction, but I seem to
>> have been
>> burned much more often than I've benefited from a pre-warmed oven.)
>>
>> 2) Is there a good command that really does leave a blank workspace? For
>> testing
>> purposes, it would be useful to have an assured blank canvas.
>
> Yes, start R with
>
> R --vanilla
>
> Duncan Murdoch
>
>>
>> This post is definitely not to start an argument, but to try to find ways to
>> reduce
>> the possibilities for unanticipated outcomes in examples.
>>
>> Cheers, JN
>>
>> ______________________________________________
>> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>>
>
______________________________________________
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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.
