Am Donnerstag 20 Januar 2005 04:41 schrieb Marc Duerner:
> I just had the idea that one could unify P::Util::Any and P::Util::Variant.
> They do basically both the same, but Any uses typeid and casting, while
> Variant (the class formerly known as LexT) uses stream based conversion.
I also had this idea.
> This would simply require to add a convertTo member function to Any that
> allows stream based conversion additionally to the any_casts:
>
> template <typename ValueType>
> ValueType convertTo(const ValueType& defVal = ValueType()) const {
> Any::holder<ValueType>* valHolder = 0;
> valHolder = dynamic_cast< Any::holder<ValueType>* >(m_data);
> if(valHolder) {
> return valHolder->value();
> }
>
> ValueType retVal(defVal);
> std::stringstream ss;
> m_data->output(ss);
> ss >> retVal;
> return retVal;
> }
>
>
> The dynamic_cast is a short cut.
>
> In code you would do this:
>
> Any myAny(5);
> string s = myAny.convertTo<std::string>();
this rocks!
> or we add a type conversion member to Any that does this automatically:
>
> template <typename T>
> operator T() const throw() {
> return this->template convertTo<T>();
> }
>
>
> Does anybody see a problem with this?
No - please merge them. Maybe we should also move Any to the P namespace.
> Marc
Greetings,
Christian
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