Bug in type inference

[Koen Claessen]

Hi,

If I load the following module:

  module Apa where
  import ST
  apa = newSTRef () >> return ()

into "ghci -package lang", and I ask for the type of "apa",
the following happens:

  Apa> :t apa
  ST () ()

This is obviously wrong, it should be (as "hugs -98" says):

  Apa> :t apa
  apa :: ST a ()

The behaviour is present in GHC 5.00.2, but has been
detected in earlier versions as well.

It does not have anything to do with GHCi, because regular
"ghc" makes the same mistake.

/Koen.