Re: [boost] quince: queries in C++ expressions

Subject: Re: [boost] quince: queries in C++ expressions
From: Mostafa (mostafa_working_away_at_[hidden])
Date: 2014-07-21 18:09:45

On Mon, 21 Jul 2014 11:45:51 -0700, Damien Buhl <damien.buhl_at_[hidden]>  
wrote:

>>> On 16/07/2014 2:14 PM, Mostafa wrote:
>> On Tue, 15 Jul 2014 18:27:07 -0700, Michael Shepanski
[snip]
>>> Out of curiosity, does the library *need* to be written in C++11, and,
>>> if so, why?
>>
>> If I tried to rewrite it in C++03, its length would multiply, if only
>> because of the need to replace variadic templates by a combinatorial
>> explosion of overloads.
>>
>> But your question was about *need*, so perhaps the uses of decltype are
>> more relevant. I do not think I could rewrite them to avoid decltype.
>> (Maybe somebody else could, but I found it hard enough without any such
>> constraint.)
>
> As I'm currently doing it for Boost.Fusion, your macro to adapt the
> types could take advantage of Boost.TypeOf which would be your
> replacement for decltype :
> http://www.boost.org/doc/libs/1_55_0/doc/html/typeof.html

That's what I figured, and Boost.Preprocessor could be used to take care  
of the variadic templates. My only concern, and maybe Michael can chime in  
here, would be the use of temporaries. In C++11 they could be moved, but  
in C++03 they may have to be copied, and I wonder if that would become  
costly with quince's design.