Re: [Boost-users] Finding member offset in compile time

17 Mar 2005

      remi.chateauneu@gmx.de schrieb:
...
To summarize, given a struct or class, you just needed one or several 
list of fields, to be able to serialize these fields only, in a specific 
order.
There were operators for serializing to a screen, creating 'CREATE 
TABLE', 'INSERT' and 'SELECT' sql queries, writing to a network socket, 
filling Windows dialogs, etc...
I had a quick look at a code example of your library and like to add 
that it is possible to do this without having to declare a list of 
members outside the class:

struct Class{
	FIELD(int,a);
};

#define FIELD(ValueT,name)
   struct _##name##_Function{
   inline void Register(){
     _RegisterField()(&This::name,#name);
   }
   }
   _ClassField name;

_ClassField is a class which behaves like a ValueT, with one difference:

template
_ClassField::_ClassField(){
   //generates _no_ code, empty inline function. is there to 
instantiated _StaticRegisterer<Function>
   _StaticRegisterer<Function>::field.Reference()
}

template<typename T>
struct _StaticRegisterer{
   static _FieldRegisterer<T> field;
};

template<typename T>
struct _FieldRegisterer{
   _FieldRegisterer();  //this gets called at program startup, _not_ at 
field construction, and registers the field.
   inline void Reference(){}
};

-- 
Stefan Strasser