#include <iostream>
#include <memory>
 
struct complex_struct
{
    void (*doSmth)();
};
 
struct complex_struct_handle
{
    // functions
    virtual void doSmth() = 0;
};
 
template<complex_struct* S>
struct csh_imp : public complex_struct_handle
{
    // implement function using S
    void doSmth()
    {
        // Optimization: simple pointer-to-member call,
        // instead of:
        // retrieve pointer-to-member, then call it.
        // And I think it can even be more optimized by the compiler.
        S->doSmth();
    }
};
 
class test
{
    public:
        /* This function is generated by some macros
           The static variable is not made at class scope
           because the initialization of static class variables
           have to be done at namespace scope.
 
           IE:
               class blah
               {
                   SOME_MACRO(params)
               };
           instead of:
               class blah
               {
                   SOME_MACRO1(params)
               };
               SOME_MACRO2(blah,other_params);
 
           The pointer-to-data template parameter allows the variable
           to be used outside of the function.
        */
        std::auto_ptr<complex_struct_handle> getHandle() const
        {
            static complex_struct myStruct = { &test::print };
            return std::auto_ptr<complex_struct_handle>(new csh_imp<&myStruct>());
        }
        static void print()
        {
            std::cout << "print 42!\n";
        }
};
 
int main()
{
    test obj;
    obj.getHandle()->doSmth();
}

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