[boost] Re: typeless trampoline

From: David Abrahams (dave_at_[hidden])
Date: 2004-09-05 12:23:35

Bronek Kozicki <brok_at_[hidden]> writes:

> Rob Stewart wrote:
>
>>>    static_assert<sizeof(Functor*) == sizeof(void *)> size;
>        ^^^^^^^^^^^^^
>>>
>>>    union convert
>>>    {
>>>      Functor* f;
>>>      void*    p;
>>>    };
>
>> What if a void * and a pmf are not the same size?  You at least
>> need a static assertion to that effect, right?
>
> Yep. I believe that it's rare, but in any case assertion is in place.

Why mess around?  You don't need to use a void*; just use a
void(X::*)(void) for any X.  Round-trip reinterpret_cast is
guaranteed to work.

-- 
Dave Abrahams
Boost Consulting
http://www.boost-consulting.com