[Haskell-cafe] data constructor names

Say you write data Callback = Error ... | ... because one of the kinds of callbacks you need to model is an error callback. Then, later, you write data Error = ... to model some error that can happen. They're both good names, but there's a conflict. So I started thinking I should prefix my constructor names like data Callback = CallbackError ... | ... It will work, but it's not the nicest looking. I discovered I can write data Callback = Callback'Error ... | ... Where can I find the syntax reference to see what's allowed? Will people kill me if I start doing this? I could import qualified, but in my case, there would be too many modules. Thanks for any advice.