/* procedure.h */

_PP_CLASS_NAME() { ... }

_PP_CLASS_NAME & operator=( _PP_CLASS_NAME const & rhs ){ ... }

... /* いろいろな共通関数とか */

-----------------------------------------
/* classes.h */

class myclass_1
{
#define _PP_CLASS_NAME myclass_1
#include "procedure.h"
#undef _PP_CLASS_NAME
...
};

class myclass_2
{
#define _PP_CLASS_NAME myclass_2
#include "procedure.h"
#undef _PP_CLASS_NAME
...
};