Thinking about Jon Lang's -1|+1 example in another way, I wondered about
simultaneous conditions.
Consider
$x = any (1,2,5,6)
How do we compose a conditional that asks if any of this set of
eigenstates are simultaneously both > 2 and < 5?
Clearly the desired answer for $x is False, but
my $x = any(1,2,5,6); say ?( 2 < $x < 5); # true
Is there some combination of any/all that will achieve this?
Here it would seem that we would want to have some sieving, so that
eigenstates that are true for one test can be given to another test.