Re: [boost] Ternary logic programming

Subject: Re: [boost] Ternary logic programming
From: Bjorn Reese (breese_at_[hidden])
Date: 2015-07-05 12:06:16

On 07/05/2015 12:10 PM, Rob Stewart wrote:

> That might be legitimate, and even useful, but doesn't it seem wrong that && and || yield the same results?

The three cases under discussion may be easier to understand if we look
at their Venn diagrams, so I have drawn them here:

   http://breese.github.io/2015/07/05/layers-of-three-valued-logic.html

(the text could be more elaborate, but I wanted to make the diagrams
available as quickly as possible.)

> If the empty state is called the same thing in each case, different behavior will be confusing. Otherwise, I agree that forcing everything into the same pattern may be more trouble than it's worth.

Indeed. The empty state may have to be called different names for the
three alternatives.