Commit 210a2e12 authored by Simon Peyton Jones's avatar Simon Peyton Jones

Test Trac #12163

parent ce97b729
{-# LANGUAGE DeriveFunctor #-}
{-# LANGUAGE GADTs #-}
module T12163 where
data T a b where
Mk :: Int -> b -> T Int b
deriving (Functor)
T12163.hs:8:16: error:
• Can't make a derived instance of ‘Functor (T a)’:
Constructor ‘Mk’ is a GADT
Possible fix: use a standalone deriving declaration instead
• In the data declaration for ‘T’
......@@ -58,4 +58,4 @@ test('T9687', normal, compile_fail, [''])
test('T8984', normal, compile_fail, [''])
test('T9968a', normal, compile_fail, [''])
test('T12163', normal, compile_fail, [''])
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