#+/-

[nelson%bach.DEC@decwrl.DEC.COM (Beryl Elaine Nelson)]

(This is in response to Don's message about nesting #+ and #-)

VAX LISP returns a two-element list whether the #+ or #- is first.
I believe that this behaviour is correct; it seems logical to 
consider the second # macro to apply to the first form to be read (1),
and the first # macro form apply to the first remaining form to
be read (1 if it hasn't been removed already, or 2 if 1 has been
removed).

Lisp> (push 'foo *features*)
(FOO EDITOR SYSTEM-EDITOR::INTERNAL-BUILD UIS COMPILER DEBUGGER VMS DEC COMMON VAX)
Lisp> '(#-foo #+foo 1 2 3)
(2 3)
Lisp> '(#+foo #-foo 1 2 3)
(2 3)

Beryl Nelson
nelson%bach@decwrl.dec.com