Re: The CRTP pattern and member function pointer template parameter
In article <1182980794.303806.163550@k79g2000hse.googlegroups.com>,
Olivier Langlois <olanglois@sympatico.ca> wrote:
Hi,
I wanted to achieve static polymorphism with the CRTP pattern to
create a base class for encapsulating the thread creation with the
pthread API. What I was trying was:
template<class D, void *(D::*F)()>
class ThreadBase
{
static void *start_routine(void *arg);
};
template<class D, void *(D::*F)()>
void *ThreadBase<D,F>::start_routine(void *arg)
{
D *pThis = static_cast<D *>(arg);
return (pThis->*F)();
}
where I could have defined a derived class:
class Derived : public ThreadBase<Derived,&Derived::Run>
{
void *Run();
};
but it does not work. GCC complains that:
incomplete type `Derived' used in nested name specifier.
Right now, I am blinded with my initial design that does not work so I
would like to ask this newsgroup readers for suggestions about the
best way solve my problem.
GCC 3.x compiles this just fine;
template<class D>
struct ThreadBase
{
typedef void *(D::*PMF)();
void *start_routine(PMF x)
{
D *p = static_cast<D *>(this);
return (p->*x)();
}
};
struct Derived:ThreadBase<Derived>
{
void *run();
};
inline void test()
{
Derived p;
p.start_routine(&Derived::run);
}
should be as useful as you thought you were getting, in that the
call is hardcoded but not ThreadBase,
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