We show that none of these type class features are necessary if weuse the single feature of extensible superclasses, the complement of subclass extension. We formalize type classes with extensiblesuperclasses as the combination of a previously introduced typepassing translation scheme and a general type class framework. Ourresults shed some new light on the use of type classes to support generic programming. 1. Introduction Generic programming is a style of programming where a singlegeneric function definition is applicable to a wide range of dat