IF-EXISTS :SUPERSEDE vs. :NEWEST

[Scott E. Fahlman <Fahlman@CMU-CS-C.ARPA>]

Bernie's arguments sound good to me.  Generating a newer file instead of
clobbering the old one seems like the least treacherous option.  If I
really do want to clobber the newest file, that's easy to do -- just
find it and ask for exactly that version to be superseded.  I might even
go farther and outlaw the use of any wild-cardish things in the pathname
given to a supersede.  After a couple of years of forced confinement on
a Tops-10 system, I have a very healthy respect for the number of subtle
ways that superseding can screw you.

To answer the specific question, CMU's Spice file-name server currently
does not provide file versions, though that will be changing any week
now.  Until we get the new name-server in Spice, we have only made a
rather half-hearted effort to implement all these options in a temporary
way -- we've done only what we need most and have not worried a lot
about the funny combinations.  So I'm afraid we provide no precedent.
I've lost track of just what the VMS implementation does on this.

By the way, we probably want to start up some sort of "Rulings on
Ambiguities" file in a generally accessible place.  Once the manual is
in print, there will still be issues like this that come up, that we
reach some sort of consensus on, and that we want to chisel into some
sort of stone (probably soapstone, not granite).  This should not
contain all the random discussion, but just the questions, answers, and
maybe some rationale.  Guy seems the obvious choise to maintain this,
unless he wants to pass the baton to someone else.

-- Scott