Re: [Boost-users] [any] Is it possible to support polymorphism in boost::any?

Subject: Re: [Boost-users] [any] Is it possible to support polymorphism in boost::any?
From: Tang Jiang Jun (tangjiangjun_at_[hidden])
Date: 2010-09-07 03:42:10

That's an excellent idea!
It's so concise and delicate to use different internal holders to represent
different sub-objects.
However I have a question about the query. How should a any object find
which holder is the correct one to the casting query for one special base
class?

Thanks!

On Mon, Sep 6, 2010 at 9:05 PM, Steven Watanabe <watanabesj_at_[hidden]>wrote:

> AMDG
>
>
> Tang Jiang Jun wrote:
>
>> After thinking deeper, I figure out a rough implementation for this idea,
>> and prove it can work with polymorphism. (It is just rough concept
>> verification, and need a lot of work to polish it and make it usable).
>>
>>
>
> A more automated way would be to use
> multiple inheritance and cross cast.
>
> class any_impl_base {
> public:
>   virtual ~any_impl_base() {}
> };
>
> template<class T, bool is_class = boost::is_class<T>::value>
> class any_impl : public T, public any_impl_base {};
>
> In Christ,
> Steven Watanabe
>
>
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