Re: [Boost-users] Is there an elegant way to initialize an instance of boost::any with a C-style string constant?

Peter Foelsche wrote:

I suggested some time ago to add a special constructor:

template any(T _ap[SIZE]);

which should do the same like any(T *_p);

Ferdinand Prantl wrote:

Well, a little shorter as the static_cast version but still a "superfluous" cast.

I could not find anything about it but the thread which I referred in the first post to. Do you remember why the constructor has not been added to the official version?

I don't know, but it makes sense to me: an array is not just a pointer! boost::any always stores a /copy/ of its constructor argument or assignment argument. So /if/ it would support built-in arrays, I think it should copy their elements internally. Still, it appears technically possible to add array support to boost::any, e.g., by having it internally hold a wrapper<ValueType>, instead of a ValueType object (as holder<ValueType>::held data member): template<typename ValueType> struct wrapper { ValueType data; explicit wrapper(const ValueType & value) : data(value) { } }; The wrapper would need to be specialized for array types, copying the array elements during construction: template struct wrapper { typename remove_const<ElementType>::type data[NumberOfElements]; explicit wrapper(const ElementType (& value)[NumberOfElements]) { std::copy(value, value + NumberOfElements, data); } }; The data member holder<ValueType>::held should be declared as wrapper<ValueType>, and references to "held" should be replaced by "held.data". Would that solve your problem in an elegant way? If so, you could consider making it a feature request :-) https://svn.boost.org/trac/boost/newticket Kind regards, -- Niels Dekker http://www.xs4all.nl/~nd/dekkerware Scientific programmer at LKEB, Leiden University Medical Center