Re: [boost] [GTL] proposal for geometry set operations

From: Simonson, Lucanus J (lucanus.j.simonson_at_[hidden])
Date: 2008-05-08 02:47:58

Simonson, Lucanus J wrote:
>> 	template <typename geometry_type_1, typename geometry_type_2>
>> 	polygon_set_view operator&(const geometry_type_1& geo1, 
>> 					const geometry_type_2& geo2) { 
>> 		...tag dispatching and so forth... }
>>   
Steven Watanabe wrote:
>I hope that this is not the actual declaration.  Completely generic 
>operator overloads
>are dangerous.

There is no declaration yet, since I haven't finalized the design.

I was thinking that it could be solved by registering the geometry types
for which operator overloading is safe as operator args in the
geometry_traits.

template <>
geometry_traits<UserPolygonSet> {
        typedef polygon_set_concept geometry_concept;
        typedef UserPolygonSet operator_arg;
};

...

template <typename geometry_type_1, typename geometry_type_2>
polygon_set_view operator&(
  typename geometry_traits<geometry_type_1>::operator_arg const& geo1, 
  typename geometry_traits<geometry_type_2>::operator_arg const& geo2);

Would this proposed solution address your concern about safety?

Is there another way to make it safe that you would suggest instead?

Thanks,
Luke