[Haskell-cafe] how to avoid overlapping instance error?

[Simon Peyton-Jones]

| Or I suppose, one could rephrase this question as why not
| simplify instance declarations to be:
| 
|    instance ToSet where
|       toSet = Set.fromList
| 
| And let the typechecker take care of figuring out what instance is
| being specified here?

That might be possible, but Haskell forces you to be a bit more
explicit, that's all.

Simon