RE: adding namespaces to emacs-lisp (better elisp?)

[Drew Adams <drew.adams@oracle.com>]

> > The symbol named "AA" with which I played there, was interned only in
> > the package named "A", and only once (in the first call to INTERN).
> > Once I've imported this symbol in the package named "B', it is visible
> > there: FIND-SYMBOL and INTERN find it.  But it's still the symbol named
> 
> Right, so there is a new notion of a symbol being "present" in an
> obarray, whereas in Emacs there's only the notion of a symbol being
> "interned" in an obarray.

Yes, but it's not new ;-), though it would be new to Emacs Lisp.  It is
30 years old.  And it was designed after years of experimentation with
different Lisp namespace ideas and implementations.

On the question of "presence" vs "accessibility" (or "appearance") in a
package, see my previous msg and CLTL(2), chapter Packages [*],
particularly the parts about a symbol being "owned" by at most one package,
its "home package".  (An uninterned symbol has no home package - no package
owns it.)

Pascal's example makes things clear.  See also the consistency rules
I quoted earlier.

[*] http://www.cs.cmu.edu/Groups/AI/html/cltl/clm/node111.html#XPACK