bug#6493:

[Drew Adams]

> > > an error seems like common sense and what users would expect.
> > 
> > That's highly subjective IMHO.
> > Do you oppose to the following (minimal) version?
> 
> Nope.  (I already said so.)

Oops, yes, I do oppose it, because it is incorrect.

What I said earlier was:
 "I have no real objection to a clear statement of the error handling."
                                ^^^^^^^^^^^^^^^

But it is incorrect that these raise an error if the region is inactive - they
do not.

emacs -Q

Visit some file.
C-SPC, then move point somewhere.
C-g to deactivate the region.
M-: (region-beginning) -> returns the value of `(mark)'.

This is with the default value of `mark-even-if-inactive' and the default of
transient-mark-mode turned on.

If you want to describe the error treatment then you need to do so completely
and correctly.  As before, I recommend against describing error handling in this
case, but I do not oppose it if done right.