bug#24369: Docu of prefix-numeric-value

[Drew Adams]

> > >     • ‘nil’, meaning there is no prefix argument.  Its numeric value
> > >       is 1,
> >
> > That's the point: Value of nil is 1
> 
> No, the _numeric_ value of nil is 1.  IOW, nil, when interpreted
> as a number, is 1.  An entirely different story.

Exactly.  The value of `(prefix-numeric-value nil)' is 1.

That's what "numeric value of" the prefix argument means.
It is also what the shorter expression "the numeric prefix
argument" means.

The fact that the value of some function applied to nil
is 1 does not mean that the value of nil is 1.