Paul's reply to my reply....
(I am hoping this gets other thinking!)

--- Forwarded mail from "Paul Taffel" <[log in to unmask]>

  In answer to your questions:

  - Write-only variables MIGHT be useful in the case where one program prompts
    the user for a password, and later on another program would like to make
use
    of the password without re-prompting, but we don't want anyone walking up
to
    the terminal to be able to :SHOWVAR and see it.

    Although I'm sure this wouldn't be as easy as I described, it might be
worth
    further investigation.

  - I suggested HELLO;NEST (or whatever else it's called) as the mechanism for
    accessing an AIFCHANGELOGON-implemented solution because of the leveraged
    benefits you'd get 'for free' at the same time: namely truly-isolated
    processes in the same tree.  Don't forget, as soon as you provide local
    variables, users will ask for local temp file domains, local file
equations,
    etc.  AIFCHANGELOGON already gives you most of this.  Also, AIFCHANGELOGON
    implements one set of 'scope rules', do you really want (or need) to
    introduce another set just for local variables?

---End of forwarded mail from "Paul Taffel" <[log in to unmask]>

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