Over a year ago, Andre wrote:
> Just a little note regarding correctness of the implementation.  The snippet
>
>          (datum->syntax
>                  #'tname
>                  `(,type-name ,fields ,parent
>                    ,(if constructor-args
>                         (list constructor-name constructor-args)
>                         constructor-name)
>                    ,predicate-name
>                    ,accessor-fields ,mutator-fields))))))
>
> is hygienically incorrect.

That has been changed in the new reference implementation, which I believe
to be hygienic (modulo its deliberate introduction of new bound identifiers).

Will