Re: [boost] Re: Formal review request: tribool library

From: Douglas Gregor (gregod_at_[hidden])
Date: 2003-10-04 11:13:13

On Saturday 04 October 2003 05:13 am, Edward Diener wrote:
> Douglas Gregor wrote:
> > I'd like to request a review of the "tribool" library. It's a little
> > 3-state
> > boolean logic library (the third state being "indeterminate", i.e.,
> > "could be
> > either true or false") that I've been using for a while in my
> > research, and
> > maybe someone else could benefit from it.
>
> In what type of situations would one use the "indeterminate" state ? Would
> you give some practical examples ? It sounds interesting.

Two more:

1) Comparing intervals in the interval library. When the intervals overlap, 
you don't know how to order the two intervals, so you need a third state to 
represent "don't know", or you need to signal a failure. See
  http://www.boost.org/libs/numeric/interval/doc/comparisons.htm

2) Determining when two pointers alias. "True" if they must alias, "false" if 
they must not alias, and "indeterminate" if they may alias.

        Doug