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From: "Johannes Schaub (litb)" <schaub-johannes@web.de>
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Subject: Re: Why is std::array an aggregate?
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Scott Meyers wrote:

> Johannes Schaub (litb) wrote:
>>
>> I believe this can all be done using variadic templates:
>>
>> template<typename T, size_t S>
>> struct array {
>>   template<typename ...U>
>>   constexpr array(U&&... u):elems{ u... } { }
>>
>>   T elems[S];
>> };
>>
>> array<int, 3> a = { 1, 2 }; // works, is statically initialized
> 
> Alas, this won't work, because you can't deduce a template argument's
> type from a brace initializer.  The standardizion people have decided
> that such a type can be deduced in the context of auto, but not a
> template.  I have no idea why.
> 

This is not deducing a template argument from a brace initializer. It will
deduce "U" against "1, 2", not against "{ 1, 2 }" (two arguments 1 and 2 are
given to the constructor), if i'm not mistaken.

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