2 tcfail001.hs:9:warning:
3 Duplicated class assertion `A a' in context: `(A a, A a)'
5 tcfail001.hs:9: Couldn't match the type
6 `PrelBase.[]' against `GHC.-> [takw]'
8 Inferred: `[takw] -> [takx]'
9 In an equation for function `op': `op PrelBase.[] = PrelBase.[]'
12 Compilation had errors