[Haskell-cafe] Re: Is this related to monomorphism restriction?

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Why isn't the last line of this code allowed? f :: (TestClass a) => a -> Integer f = const 1 a = (f,f) g = fst a The only thing I can think about is monomorphism restriction, but it's allowed (...)

(...) The reason is that a has type a :: (TestClass a, TestClass b) => (a,b) and then when we take 'fst' of this value (as in g) we get

g :: (TestClass a, TestClass b) => a which is an ambiguous type, (...)

Is there some version (i.e., set of extensions) of Haskell where this would be allowed?