Re: [boost] Interest in DSL framework

From: Joel de Guzman (joel_at_[hidden])
Date: 2006-08-13 19:37:13

Andy Little wrote:
> "Andreas Pokorny" <andreas.pokorny_at_[hidden]> wrote in message
> <...>
> 
>>  // rules:
>>  template<typename EnableIfT>
>>  struct rule<example_domain,right_shift_tag,A,B,EnableIfT>
>>    : defined, mpl::true_
>>  {
>>     typedef TYPE_WHICH_ENCODES_THE_EXPRESSION result_type;
>>     static result_type init(A const& a, B const& b) { return
>> result_type(...); }
>>  };
>>
>>  template<typename EnableIfT>
>>  struct
>> rule<example_domain,bitor_tag,TYPE_WHICH_ENCODES_THE_EXPRESSION,C,EnableIfT>
>>    : defined, mpl::true_
>>  {
>>     typedef TYPE_WHICH_ENCODES_THE_WHOLE_TREE result_type;
>>     static result_type init(A const& a, B const& b) { return
>> result_type(...); }
>>  };
> 
> I don't understand what these TYPE_WHICH_ENCODES_THE macros are, but can 't you
> use Boost.Typeof for this?

IIUC, the "rule" specifies the result type (not deduces the
result type). I think it's not a macro at all; it would rather
be something like: "unspecified_type", or
"you-define-your-type-here-and-ill-do-the-rest"

Regards,
-- 
Joel de Guzman
http://www.boost-consulting.com
http://spirit.sf.net