-\r
-tcfail157.hs:27:10:\r
- Variable `b' occurs more often than in the instance head\r
- in the constraint: E m a b\r
- (Use -XUndecidableInstances to permit this)\r
- In the instance declaration for `Foo m (a -> ())'\r
-\r
-tcfail157.hs:27:10:\r
- Variable `b' occurs more often than in the instance head\r
- in the constraint: Foo m b\r
- (Use -XUndecidableInstances to permit this)\r
- In the instance declaration for `Foo m (a -> ())'\r
+
+tcfail157.hs:27:10: error:
+ • Variable ‘b’ occurs more often
+ in the constraint ‘E m a b’
+ than in the instance head ‘Foo m (a -> ())’
+ (Use UndecidableInstances to permit this)
+ • In the instance declaration for ‘Foo m (a -> ())’