Tue, 4 Sep 2001 20:28:55 +0300, Eray Ozkural pisze:

Okay, I guess I got it now. The (types of) elements of a Set ought to be instances of Ord. So I presume Edison supports only flat sets.

You can add an inefficient implementation of Ord (Set a) yourself: instance Ord a => Ord (Set a) where compare s1 s2 = compare (toOrdList s1) (toOrdList s2) toOrdList seems to be exported only module Collection. If more than one module does this, they can't be used together. -- __("< Marcin Kowalczyk * qrczak@knm.org.pl http://qrczak.ids.net.pl/ \__/ ^^ SYGNATURA ZASTÊPCZA QRCZAK