3 Could not deduce (Num a)
4 arising from the superclasses of an instance declaration
5 from the context: (Eq a, Show a)
6 bound by the instance declaration at tcfail042.hs:15:10-34
8 add (Num a) to the context of the instance declaration
9 In the instance declaration for ‘Bar [a]’
12 Could not deduce (Num a) arising from a use of ‘foo’
13 from the context: (Eq a, Show a)
14 bound by the instance declaration at tcfail042.hs:15:10-34
16 add (Num a) to the context of the instance declaration
17 In the expression: foo xs
18 In an equation for ‘bar’:
24 In the instance declaration for ‘Bar [a]’