R help - May 2011 - Why do not prevent users from creating a local copy of c() ?

Hi all,

sometime in the past I accidentaly created a copy of the c()
primitive function inside my ``laboratory'' workspace, which I
normally use to experiment and learn. As a consequence, c() stopped to
work correctly and started to return lists of symbols instead of
vectors, and today I had to spend much time to seek out that the problem
was in that specific workspace (if only I had known in advance ... ). 

The weird thing is that if I now recreate a local copy of c(), the
function does continue to work correctly.

Anyway, my question is: could be possible to prevent users from doing
such dangerous things? 

Thanks, Marco.

There is no way to prevent a user from messing up.  No matter how many
things you put in to prevent such occurances, I have always found that
users find new ways to use your system that you never considered.

There is always the 'conflicts()' function that might help:
> # create my 'c'
> c <- function(x) x
> conflicts()
[1] "body<-"  "c"       "setwd"  
"summary"
>


On Sun, May 29, 2011 at 3:20 PM, Marco Barb?ra <jabbba at gmail.com>
wrote:
> Hi all,
>
> sometime in the past I accidentaly created a copy of the c()
> primitive function inside my ``laboratory'' workspace, which I
> normally use to experiment and learn. As a consequence, c() stopped to
> work correctly and started to return lists of symbols instead of
> vectors, and today I had to spend much time to seek out that the problem
> was in that specific workspace (if only I had known in advance ... ).
>
> The weird thing is that if I now recreate a local copy of c(), the
> function does continue to work correctly.
>
> Anyway, my question is: could be possible to prevent users from doing
> such dangerous things?
>
> Thanks, Marco.
>
> ______________________________________________
> R-help at r-project.org mailing list
> 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.
>


-- 
Jim Holtman
Data Munger Guru

What is the problem that you are trying to solve?

Hi Marco,

I am sure theoretically it would be possible to make it so that copies
could not be made of base (or core) functions, but users will always
be able to shoot themselves in the foot if they try hard enough.  I
think the usual recommendation is just not to use common function
names for your own functions/data.

If you write scripts instead of just directly using the console, you
do not need to save the workspace, which mitigates a whole slew of
potential things you did at some prior time and have long since
forgotten biting you in the posterior.  You can still save data, but
by using clean sessions, you are more aware of what has been done.

Cheers,

Josh

On Sun, May 29, 2011 at 12:20 PM, Marco Barb?ra <jabbba at gmail.com>
wrote:
> Hi all,
>
> sometime in the past I accidentaly created a copy of the c()
> primitive function inside my ``laboratory'' workspace, which I
> normally use to experiment and learn. As a consequence, c() stopped to
> work correctly and started to return lists of symbols instead of
> vectors, and today I had to spend much time to seek out that the problem
> was in that specific workspace (if only I had known in advance ... ).
>
> The weird thing is that if I now recreate a local copy of c(), the
> function does continue to work correctly.
>
> Anyway, my question is: could be possible to prevent users from doing
> such dangerous things?
>
> Thanks, Marco.
>
> ______________________________________________
> R-help at r-project.org mailing list
> 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.
>


-- 
Joshua Wiley
Ph.D. Student, Health Psychology
University of California, Los Angeles
http://www.joshuawiley.com/