Re: Comment on my adapter concept

  Well it irons your shirts, feeds your kids, walks the
dog and pays the mortgage :-)

  It's just a C-Style plugin system where each time a new
plugin is meant to be written a couple of function pointers
have to be initialized to NULL or a valid function pointer.
The whole code is very C++-stylish already. They have
structs mimicking a std::string and things that look
like a streambuf. So I'm covering this all under a
C++-layer.

So e.g. something like

int_plugin(*p) {
   p->alloc = my_alloc;
   p->free = my_free;

   p->do_foo1 = NULL;
   p->do_foo2 = my_do_foo2;
   ...
   ...
   ...
}

becomes

int_plugin<M>(*p) {
   p->alloc = module_adapter<M>::alloc;
   p->free = module_adapter<M>::free;
   p->do_foo1 = module_adapter<M>::do_foo1;
   ...
   ...
}

Notice that the second function is module independent
"do_foo1" will become NULL whenever the module class
doesn't declare a do_foo1 method. Whereas the first
approach has to be rewritten whenever the module interface
changes. This goes down to the module_traits<M>::has_function::do_xyz
enum. In my example code these values are set explicitly, but
I already check via SFINAE if the corresponding method exists.

Hope that explains why

O.

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