Re: [Boost-users] [Boost users] [interprocess]: static_pointer_cast on offset_ptr

From: Ion Gaztañaga (igaztanaga_at_[hidden])
Date: 2007-10-31 11:23:38

Lars Hagström escribió:
> Yes, but it has to be safer and more correct to use static_pointer_casts
> instead of reinterpret_cast.
> In my particular situation I am unfortunately not able to use templates,
> so I do need to do "ugly" pointer stuff.
> (I am porting an existing shared-memory solution to boost::interprocess).
> 
> I've uncommented the static_pointer_cast et al functions from
> offset_ptr.hpp, and they appear to do their work beautifully.
> 
> Lars

Sorry for the late reply. Originally I wrote static_pointer_cast & co. 
functions to mimic shared_ptr. I even used them as generic casting 
function for code where the pointer type is templated.

However, those functions need an explicit template argument so ADL was 
not activated (say, like when you use an unqualified swap call). In the 
end I decided to comment them to prevent users using them (I should have 
erased them...).

You can achieve the same using:

offset_ptr(static_cast<MyType*>(my_offset_ptr.get()));

without any performance hit, so I didn't consider them essential (ok, 
you have to type more ;-)). Is there any reason why you prefer 
static_pointer_cast instead of the code above? I have no problem to 
uncomment the code if you find it useful.

Regards,

Ion