testsuite: Assert that testsuite ways are known
[ghc.git] / testsuite / tests / typecheck / should_compile / T10562.hs
1 {-# LANGUAGE GADTs, TypeFamilies #-}
2 module T10562 where
3
4 type family Flip a
5
6 data QueryRep qtyp a where
7 QAtom :: a -> QueryRep () a
8 QOp :: QueryRep (Flip qtyp) a -> QueryRep qtyp a
9
10 instance Eq (QueryRep qtyp a) where
11 (==) = error "urk"
12
13 instance (Ord a) => Ord (QueryRep qtyp a) where
14 compare (QOp a) (QOp b) = a `compare` b