[boost] Re: Interval Library and comparison operators

From: Dave Gomboc (dave_at_[hidden])
Date: 2002-09-05 13:49:46

> >   1) Don't support any comparison operators, or
> >   2) Use comparison policies
> 
>     3) Pick a fixed meaning for the comparison operators, and provide
> function (object)s for the other kinds of comparison.

Judging from the variety of different, conflicting definitions that other
interval arithmetic libraries use, and the varied proposals that Boosters
have brought forth, it seems that no particular comparison operation has a
clearly most valid claim to operator<= and the like.  Therefore, I don't
think that assigning one meaning to them is appropriate: no matter the
definition selected, mnay users would find it counter-intuitive and expect
an alternate definition.  I think it would be best if all 13 relations
Joel Young suggested be provided (meets, precedes, etc.) and either of the
following done:

    a) prohibit definition of relational operators such as <= entirely
       (declare them private and do not define them)
or
    b) allow the library user to overload the relational operators
       as they see fit for their application (which is easily done if
       implementations of the 13 relations are already provided).

Dave