[Haskell-cafe] Possible bug?

Tillmann Rendel rendel at cs.au.dk
Fri Feb 13 12:26:18 EST 2009

Peter Verswyvelen wrote:
> Could it be considered a bug when a function compiles fine without type 
> signature, but when you add the type signature that GHCi reports with 
> :type, it fails to compile?

There are such cases where it is not a bug. For example, given

   import Data.Map (fromList)

   x a = fromList a

ghci will happily report that x has type

   Ord k => [(k, a)] -> Data.Map.Map k a

but the name Data.Map.Map is not in scope in the module.


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