2 tcfail019.hs:20: No instance for:
5 in an instance declaration
6 When checking methods of an instance declaration
8 tcfail019.hs:20: No instance for:
11 in an instance declaration
12 When checking methods of an instance declaration
14 tcfail019.hs:20: No instance for:
17 in an instance declaration
18 When checking superclass constraints of an instance declaration
20 tcfail019.hs:20: No instance for:
23 in an instance declaration
24 When checking superclass constraints of an instance declaration
27 Compilation had errors