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Re: (il)logical algebra

2004-03-25 05:05:03
On Thu, Mar 25, 2004 at 12:30:22PM +0100, Dallman Ross wrote:

reverse De Morgan recipe set.

   :0
   * ! ^Blacklist: Yes
   *   ^Whitelist: Yes
   { }

   :0 E
   do_something


If you really want OR-NOT, you can do it this way, but it seems
not nearly as elegant to me:

  :0
  * (^Blacklist: Yes| ! ^Whitelist: Yes)
  do_something

I should have mentioned the third way of ORing: weighted conditions.

  :0
  * 1^0    ^Blacklist: Yes
  * 1^0  ! ^Whitelist: Yes
  do_something


Perhaps you like that better.  If you care to optimize it, use
a weight equal to or greater than procmail's highest calculated
number (see "man procmailsc").  We often refer to that limit
as "infinity" (or even $INFINITY) in procmail-speak.  Instead
of trying to remember 2**34-1, you can just use the large number
that is mnemonically ("Eselbrueckweise") easy:


  :0
  * 9876543210^0    ^Blacklist: Yes
  * 9876543210^0  ! ^Whitelist: Yes
  do_something


Amazing what the first cup of (late-) morning coffee brings, eh? :-)

Tschuess,
Dallman

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