Re: [Boost-users] C++ Template Metaprogramming Book - Chapter 4

Yes Felipe, I am :-) Obrigado pela ajuda On 6/19/06, Felipe Magno de Almeida wrote:

On 6/19/06, Eduardo Bezerra wrote:

...

Hi,

In C++ Template Metaprogramming chapter 4, item 4.1.2. Lazy Type Selection typename is_scalar<T>::type and is_scalar<T> can be used interchangeably as in the example below:

[snipped example]

...

I'm still trying to figure out the reason why.

I understand that to invoke a metafunction you have to reach into its nested ::type member and I also know that integral constant wrappers have a ::value member.

is_scalar<T> inherits from true_type or false_type, which work for both concepts: integral constant (::value) and nullary-metafunction (::type).

...

Any help would be greatly appreciated

Regards, Eduardo

PS: Are you from brazil? -- Felipe Magno de Almeida Consultor - Expertise Solutions http://www.expertisesolutions.com.br _______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users