Would we consider type class directives, as in: http://www.cs.uu.nl/~bastiaan/padl05-heeren-slides.pdf http://www.cs.uu.nl/~bastiaan/hh05classdirs.pdf The idea is that there are some modifiers to class declarations: never close disjoint default I assume the committee knows these better than I, but a short summary for those who haven't sen these before is that: never adds prevention of particular absurdities: never Eq (a ->b) close restricts classes to particular areas: close Integral (Int, Integer) disjoint (Integral, Fractional) and defaulting is discussed http://hackage.haskell.org/trac/haskell-prime/ticket/21 Jim