On Mon, 12 May 2003 09:56:02 +0100 (BST), Philip Hazel wrote:
[...]
><nice explanation snipped>
>
>Another way of understanding this is to read ACLs with AND between each
>line. That's why the order of the two "domains" in the first example
>doesn't matter (except for performance considerations).
>
>Reading domain lists is a bit more complicated. You need to put OR after
>a positive item, and AND after a negative item. So the domain list in
>the second example above is
>
> NOT EXIM_VIRT_DOM_DIR/no_callout AND +local_domains
>
>If you wrote those two items the other way round, the meaning would be
>
> +local_domains OR NOT EXIM_VIRT_DOM_DIR/no_callout
>
>which is not the same thing.
You must be a mathematician specializing in Boolean logic. ;-)
Seriously, your explanation is also a good one. Thanks!
One last question: Do the implicit AND/OR association "weights" ("AND"
stronger than "OR") apply? I.e. "c OR a AND b" == "c OR (a AND b)"? Or do we
have a strict left-to-right logic, i.e. "c OR a AND b" == "(c OR a) AND b"?
Cheers,
Ralf
--
L I N U X .~.
The Choice /V\
of a GNU /( )\
Generation ^^-^^
