source: tests/exceptions/virtual-poly.cfa @ dafbde8

// Test virtual casts with polymorphic types.

/* IMPORTANT: The virtual system has not been finalized. However the
 * exception system does depend on the work-in-progress version currently
 * supported. That is also why the tests under the exception directory.
 */

#include <assert.h>

struct mono_base_vtable {
        mono_base_vtable const * const parent;
};

struct mono_base {
        mono_base_vtable const * virtual_table;
};

forall(T)
struct mono_child_vtable {
        mono_base_vtable const * const parent;
};

forall(T)
struct mono_child {
        mono_child_vtable(T) const * virtual_table;
};

mono_base_vtable _mono_base_vtable_instance @= { 0 };
mono_child_vtable(int) _mono_child_vtable_instance @= {
        &_mono_base_vtable_instance
};

void mono_poly_test(void) {
        mono_child(int) child = { &_mono_child_vtable_instance };
        mono_base * base = (virtual mono_base *)&child;
        assert(base);
}

forall(U)
struct poly_base_vtable {
        poly_base_vtable(U) const * const parent;
};

forall(U)
struct poly_base {
        poly_base_vtable(U) const * virtual_table;
};

forall(V)
struct poly_child_vtable {
        poly_base_vtable(V) const * const parent;
};

forall(V)
struct poly_child {
        poly_child_vtable(V) const * virtual_table;
};

poly_base_vtable(int) _poly_base_vtable_instance @= { 0 };
poly_child_vtable(int) _poly_child_vtable_instance @= {
        &_poly_base_vtable_instance
};
/* Resolver bug keeps me from adding these.
poly_base_vtable(char) _poly_base_vtable_instance @= { 0 };
poly_child_vtable(char) _poly_child_vtable_instance @= {
        &_poly_base_vtable_instance
};
*/

void poly_poly_test() {
        poly_child(int) child = { &_poly_child_vtable_instance };
        poly_base(int) * base = (virtual poly_base(int) *)&child;
        assert(base);
}

int main(void) {
        mono_poly_test();
        poly_poly_test();
        printf( "done\n" );                             // non-empty .expect file
}