The Haskell 1.4 Report (Section 5.3.1) states
The Prelude module is always available as a qualified import: an
implicit `import qualified Prelude' is part of every module and names
prefixed by `Prelude.' can always be used to refer to entities in the
Prelude.
However, compiling the following program under GHC 2.02 (alpha-dec-osf2)
module M (myfoldr) where
import Prelude hiding (foldr)
myfoldr = Prelude.foldr
produces the following error message
% ghc bug.hs
bug.hs:5: value not in scope: Prelude.foldr
Compilation had errors
Chris