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From: Ion Gaztañaga (igaztanaga_at_[hidden])
Date: 2006-06-15 15:04:03

> what is your basis for that assertion?

Because I wrote that header thinking (wrongly, because of my ADL
ignorance and VC support) that it would be used for ADL lookup:

// (C) Copyright Ion Gaztañaga 2005.
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at


namespace boost {

//static_pointer_cast overload for raw pointers
template<class T, class U>
inline T* static_pointer_cast(U *ptr)
    return static_cast<T*>(ptr);


} // namespace boost


I wrote this because I wanted to use it though ADL. If
static_pointer_cast<Target>() can't be used through ADL, it's certainly
a very limited header. Unless I know that my pointer can be a raw
pointer, I know all the possible pointer types and I include all the
headers, this header is useless. Until Boost 1.34 this header didn't exist.

But I still see a need for customizable cast functions. Since shared_ptr
is de-facto standard, I'm just proposing new generic cast functions.
What about template specialization?:


namespace boost {

template<class TargetPtr>
class cast_to;

template<class T>
class cast_to<T*>
   template<class Source>
   static T * using_static_cast(Source *source)
   { return static_cast<T*>(source); }

} //namespace boost {

namespace boost {


template<class T>
class cast_to<smart_ptr<T> >
   template<class Source>
   static smart_ptr<T>
     using_static_cast(const smart_ptr<Source> &source);

} //namespace boost {

// pointer independent code

BasePtr d_ptr = ...

typedef typename
    boost::pointer_to_other<BasePtr, Base>::type DerivedPtr;

DerivedPtr target = cast_to<DerivedPtr>::using_static_cast(b_ptr);


Sorry if there are errors in the code. Any suggestion? Time to request
cast operator overloading for user classes?



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