On Sun, Oct 21, 2001 at 07:56:08PM +0100, Simon Cozens wrote: > On Wed, Oct 10, 2001 at 11:27:24AM +0200, Paolo Molaro wrote: > > ... and to go a step further in sanity and maintainability, I'd suggest > > using a structure with properly typed function pointers instead of an > > array: > > > > typedef void (*parrot_pmc_add) (PMC *dest, PMC *a, PMC *b); > > typedef void (*parrot_pmc_dispose) (PMC *cookie); > > ... > > I've now changed the vtable structure to reflect this, but I'd like someone to > confirm that the "variant" forms of the ops can be addressed the way I think > they can. (ie. structure->base_element + 1 to get "thing after base_element")
If you mean vtable->add_1 + 1 gives you vtable->add_2, no. Pointer arithmetic on a function pointer is not meaningful. You probably want to use an array of function pointers for each method, like add[7] and initialize each entry with the appropriate function pointer. -- Jason
