2 tcfail019.hs:20: No instance for: `B [tal6]'
3 arising from an instance declaration at tcfail019.hs:20
4 When checking methods of an instance declaration
6 tcfail019.hs:20: No instance for: `C [tal6]'
7 arising from an instance declaration at tcfail019.hs:20
8 When checking methods of an instance declaration
10 tcfail019.hs:20: No instance for: `B [tal6]'
11 arising from an instance declaration at tcfail019.hs:20
12 When checking superclass constraints of an instance declaration
14 tcfail019.hs:20: No instance for: `C [tal6]'
15 arising from an instance declaration at tcfail019.hs:20
16 When checking superclass constraints of an instance declaration
19 Compilation had errors