[R] problem with package development and older defs earlier in search order

[Rolf Turner]

On 10/11/12 12:08, Martin J Reed wrote:
> Rolf and Duncan
>
> Many thanks. Your answers pointed me to a refinement that is closer to what I want:
>
>    rm(list=intersect(ls(".GlobalEnv"),ls("package:reedgraph")),
>       pos=".GlobalEnv")
>
> This only removes items that are "masked" by GlobalEnv from my package.
>
> As this is a bit long for some of the people that need to update their workspaces I have created a function to fix it:
>
> <packagename>.update2package  <- function() {
>    rm(list=intersect(ls(".GlobalEnv"),ls("package:<packagename>")),
>       pos=".GlobalEnv")
> }
>
> Just for completeness (if anyone else reads this). It is possible to make this happen automatically at package load using
>
> .onAttach <- function(libname, pkgname) { <packagename>.update2package() }
>
> However, as Duncan says this is REALLY bad practice, but is useful to me while debugging….

I really don't see it as being at all useful.  What is the point, in 
terms of package
development, of keeping copies of those functions in the global 
environment if
you are going to remove them whenever you load the package?

It sounds to me like you need to implement some system of version control,
such as subversion (svn).  Personally I use rcs --- simple enough for 
the simple
minded such as my very good self to use, and amply adequate for my needs.

A version control system allows you to "backtrack" if a revision that 
you make
to a bit of software turns out to be undesirable.  It will do that much more
effectively IMHO than your current shaganappi strategy.

Finally you should note that CRAN policies expressly forbid the sort of 
thing that you
propose doing with your .onAttach() function,  should you ever be 
inclined to submit
your package to CRAN.

     cheers,

         Rolf