>>Gordon Henriksen <malic...@mac.com> wrote:

>>>... Best example: morph. morph must die.

>>Morph is necessary. But please note: morph changes the vtable of
>>the PMC to point to the new data types table. It has nothing to do
>>with a typed union.

>The vtable IS the discriminator. I'm referring to this:

>    typedef union UnionVal {
>        struct {                    /* Buffers structure */
>            void * bufstart;
>            size_t buflen;
>        } b;
>        struct {                    /* PMC unionval members */
>            DPOINTER* _struct_val;   /* two ptrs, both are defines */
>            PMC* _pmc_val;
>        } ptrs;
>        INTVAL int_val;
>        FLOATVAL num_val;
>        struct parrot_string_t * string_val;
>    } UnionVal;

>So long as the discriminator does not change, the union is type stable.