[boost] proto "boolean" laws (was Re: proto::tag naming convention

29 Apr 2007

      On 04/27/2007 03:25 PM, Eric Niebler wrote:
...
Larry Evans wrote:
...
why not
do the following renames:
proto::_       -> proto::true_
proto::not_<_> -> proto::false_
?
No, proto::_ is a placeholder. And proto::not_<> can logically negate 
any grammar, not just proto::_.
Actaully, the following is what I had in mind:

namespace boost
{
namespace proto
{
       struct
     true_
     : _
     {};
       struct
     false_
     : not_<true_>
     {};

}}//exit boost::proto namespace

Why?  Because I think (I haven't tested it) the same
laws for mpl::bool_ and it's associated operations:

   mpl::not_
   mpl::and_
   mpl::or_

would apply to proto's true_, false_, not_,....