On 11/04/2020 19.26, Štěpán Němec wrote:
> This is incorrect, as witnessed by your very example (`c' instead of
> `b'). Records are accessible with `aref', but the first slot is the type
> descriptor, so you're making an off-by-one error here.

Of course, it should be `for slot in (cl-struct-slot-info (type-of a))` not `for slot in (cdr (cl-struct-slot-info (type-of a)))`.  Updated patch attached.

Thanks for the review!