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Subject: Re: [boost] [1.44] Beta progress?
From: Matthias Troyer (troyer_at_[hidden])
Date: 2010-07-27 11:58:05


On 27 Jul 2010, at 09:09, David Abrahams wrote:

> At Mon, 26 Jul 2010 12:07:16 -0600,
> Matthias Troyer wrote:
>>
>>> I see the utility of augmenting STRONG_TYPEDEF but
>>> I wonder about it. if you have code T:base_type and
>>> T is not one of the types we're using - it won't have
>>> this available - compiler error. Wouldn't it be better
>>> to specify the implicit requirements as above and just
>>> know that T will be converted to what one wants? and
>>> sizeof(T) can be applied to both the (now) more elaborate
>>> types as well as C++ primitives.
>>
>> The only problem I see with sizeof(T) is that it cannot tell me
>> about signedness. Otherwise I could hack it from sizeof(T)
>
> You should get the nested typedef; that is the non-hack solution.
> That said, I could write you a metafunction to discover signedness if
> you need it.

I can also write a meta function that will tell me which integral conversion is preferred and from that deduce the type, but that is indeed more prone to compiler bugs or other problems than a nested typedef.


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