Sean Leather wrote:

...

example = zip [1,2::Int] ['a','b'] ["1","b"] :: [(Int,Char,String)]

BTW, I realized that this example also works in yours. You weren't giving enough type annotations.

Yes, exactly. Or in other words, the class definition does not correctly specify the dependencies. That is what I am writing in about -- I don't want clients to 'zip' to be required to put all those type annotations in. -- _jsn