Re: [boost] [fusion] unpack into constructor?

From: Eric Niebler (eric_at_[hidden])
Date: 2007-06-15 14:10:10

Peter Dimov wrote:
> Eric Niebler wrote:
>> Tobias Schwinger wrote:
>>> Tobias Schwinger wrote:
>>>
>>>>         // [...] tricky nullary case with default ctor detection
>>>>         // omitted for simplicity
>>>>
>>> Doh! It's not possible to detect default constructibility, correct?
>>>
>>> So we'd have to declare it as
>>>
>>>      template<typename T, typename DefaultConstructible =
>>>      mpl::false_> struct constructor;
>>
>> No. If the interface is "construct<T>(sequence)", then you can
>> dispatch on the size of the sequence. You'd only try to default
>> construct when you pass an empty sequence.
> 
> Why is there a need to detect a default constructor?

There isn't one, as far as I can tell.

-- 
Eric Niebler
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