  The interpolation-based decoding that was developed for general evaluation AG
codes is shown to be equally applicable to general differential AG codes. A
performance analysis of the decoding algorithm, which is parallel to that of
its companion algorithm, is reported. In particular, the decoding capacities of
evaluation AG codes and differential AG codes are seen to be nicely
interrelated. As an interesting special case, a decoding algorithm for
classical Goppa codes is presented.
