Lemma reptype_Tarray_JMeq_constr1: forall t gfs t0 n a i (v: reptype (nested_field_type t (ArraySubsc i :: gfs))), legal_nested_field t gfs -> nested_field_type t gfs = Tarray t0 n a -> {v': reptype (gfield_type (nested_field_type t gfs) (ArraySubsc i)) | JMeq v v'}.