gitlab-ci: Move hadrian-ghc-in-ghci job first
[ghc.git] / testsuite / tests / typecheck / should_compile / T4401.hs
1 {-# OPTIONS_GHC -fno-warn-redundant-constraints #-}
2 {-# LANGUAGE FlexibleInstances, UndecidableInstances,
3 MultiParamTypeClasses, FunctionalDependencies #-}
4 module T4401 where
5
6 class Mul x y z | x y -> z
7 class IsType a
8 class IsType a => IsSized a s | a -> s
9
10 data Array n a = Array
11 instance IsSized a s => IsType (Array n a)
12 instance (IsSized a s, Mul n s ns) => IsSized (Array n a) ns