[R] Why is rm(list=ls()) bad practice?

[J C Nash]

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. 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.

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